WO2020060887A2 - Enzyme-inspired metal-organic framework - Google Patents

Abstract

Metal-organic framework (MOF) catalysts comprise metalated imidazole-based ligands which form a reactive metal-oxygen complex within the MOF.

Description

Enzyme-inspired metal-organic framework

This invention was made with government support under Contract/Grant Number DE- AC02-05CH11231 awarded by the U.S. Department of Energy The government has certain rights in the invention.

[001] Introduction

[002] Selective methane oxidation to methanol represents an important challenge in catalysis due to the difficulty in activating the strong C ί 1 bond of methane (bond dissociation energy = 104 kcal moF ), giving rise to selectivity and activity problems . Finding a solution to this impediment is a key toward the direct synthesis of methanol from methane^{9 1}. In nature, particulate methane monooxygenase (pMMO) is an effective catalyst for the oxidation of methane to methanol , and its structure has been studied ^" .

[003] Inspired by pMMO, molecular complexes have utilized the tunability of ligand design in pursuit of duplicating the structure and reactivity in a synthetic system. A library of compounds with various copper-oxygen complexes have been reported, including but not limited to Cu₂0₂ [trans- 1 ,2-peroxo, m-h \h -peroxo and bis(u-oxo)dicopper cores] and Cu₂0 [mono(w-oxo) dicopper core] along with their spectroscopic fingerprints . Despite such vast library of compounds, the reactivity of this class of catalysts are generally limited to substrates with weak C-H bonds due to the restricted thermal stability¹⁹. At elevated temperatures, these compounds are susceptible to decomposition via ligand oxidation and thus the loss of catalytically active copper-oxygen cores . Although there exist synthetic catalysts capable of partial methane oxidation such as Cu-exchanged zeolites, the diversity of the active sites are limited to mono(«- oxo)dicopper and tris(w-oxo)tricopper cores^3,5’²¹. These catalysts typically operate in step-wise treatment for partial methane oxidation: (1) catalyst oxidation, (2) methane activation, and (3) methanol extraction, proceeding at different reaction temperatures, thus presenting a challenge for a streamlined catalytic process.

[004] The active sites of metalloenzymes are typically enclosed in a pocket for environmental control, hydrogen bonding, ion transport or controlling the reaction to prevent self-destruction" ^2b. We envisaged that metal-organic frameworks (MOFs)^{2 ,} can serve as a scaffold akin to the polypeptide chains in enzymes whose arrangement of secondary and tertiary structures can be achieved by judicious choice of structure and topology of MOFs ^' . The metal binding ligands bearing an imidazole unit in the copper active site of pMMO can be mirrored in a synthetic system by post-synthetic modification of MOFs^{32 34}. Once these metal-binding ligands are in place, metalation with the desired configuration can be accomplished³⁵’^·56.

[005] Here, we demonstrate how MOFs can be used as a backbone for the creation of an enzyme-like active site by installing biologically relevant imidazole moieties, then subsequently metalating these ligands to incorporate a variety of reactive metal-oxygen complexes within the framework. The resulting catalysts are capable of highly selective catalytic activity, typically under isothermal conditions.

[006] The modularity in choosing the metals and imidazole-based ligands in this approach provides a direct route to systematically tune the reactivity of the active site. As examples, using this technique, metalation of iron and zinc in MOF bearing imidazole moieties can be employed to have structural similarity to sMMO and CAII, respectively where sMMO is a methanotroph that oxidizes methane to form methanol using atmospheric oxygen and carbonic anhydrase (CA) is a ubiquitous zinc metalloenzyme that catalyzes the reversible hydration of carbon dioxide. Both methane and carbon dioxide are challenging gas molecules to catalyze under mild reaction conditions; this invention provides for converting both molecules to useful chemicals via enzyme-inspired MOFs, with diverse applications such as shale gas conversion to methanol, carbon sequestration, etc.

[ )07] Summary of the Invention

[008] In an aspect the invention provides a composition comprising a metal-organic framework (MOF) catalyst comprising metalated azole ligands which form a reactive metal- oxygen complex within the MOF.

[009] I n embodiments :

[0111] the MOF is metalated with Cu, Fe or Zn;

[Oil] the ligands are imidazole-, pyrazole- and/or triazole ligands, preferably imidazole ligands, preferably selected from L-histidine, 4-imidazoleacry!ic acid and 5- benzimidazolecarboxyiic acid;

[012] the MOF is selected from MOF-808, 2¾0₄(0H)₄(BTC)₂(HC00)₅ (H₂0), (OFF)i ,

BTCHbenzenetricarboxylate], PCN-777 [Zr₆(0)₄(OH)io(H₂0)₆(TATB)₂, 4, 4’, 4’’-s-triazine-2,4,6-triyl- tribenzoate], MOF -545 [Zr₆0₈(H₂0)g(TCPP-FI₂)₂, TCPP-H₂ ^:=^:tetrakis(4-carbox> henyl)porphyrin], NU-1000 [Zr₆0₄(0H)₄(0H)₄(0Ii₂)₄(TBAPy)₂, 1 ,3,6,8-teirakis{p-benzoate)pyrene], PCN-133

[Zr₆0₄(0H)₄(BTB)₂(DCDPS)₃, BTB = l,3,5-tris(4-carboxyphenyl)benzene, DCDPS = 4,4’-dicarboxydiphenyl sulfone], PCN-134 lZr_ft0₄(t⁾l S )_L(I !₂0)₂(B^'j B}₂( ! CPP-i h}, BTB - l ,3^-tris(4-caiboxyphenyl)benzene, TCPP- H₂ = tetrakis(4-carboxyphenyl)porphyrin)], PCN-224 [Zr₆0₄(0H)₄(H₂0)₆(0H)₆(TCPP-H₂)i_.5, TCPP-H₂ = tetrakis(4~carboxyphenyi)porphyrin)], MOF-802 [Zr₆0₄(0H)₄(PZDC)₅(HC00)₂(H₂0)₂, PZDC = 1 H-

? pyrazole-3,5-dicarboxylate), MOF-841 [Zr₆0₄(0H)₄(MTB)₂(HC00)₄(H₂0)₄, MTB = 4,4',4",4"'- methanetetrayltetrabenzoate], and DUT-67 [Zr₆0₄(0H)₂(TDC)₄(CH₃C00)₄, TDC = thiophene-2 ,5- dicarboxylate];

[1)13] the composition provides catalytic activity selected from methane oxygenase, carbonic anhydrase and alcohol dehydrogenase;

[014] the composition provides methane oxygenase activity, and comprises reactants and/or products of the activity [methane, N₂0, 0₂, NAD(P)H to methanol, N₂, water, and NAD(P)];

[015] the composition provides carbonic anhydrase activity, and comprises reactants and/or products of the activity (carbon dioxide, water to carbonic acid);

[016] the composition provides alcohol dehydrogenase activity, and comprises reactants and/or products of the activity (alcohol (e.g ethanol), NAD⁺ to aldehyde (e.g. acetaldehyde),

NADH).

[017] In an aspect the invention provides methods of making the subject compositions, such as comprising metalating the ligands to incorporate reactive metal-oxygen complexes within the MOF.

[018] In an aspect the invention provides methods of using the subject compositions such as forming a mixture of the catalyst and reactants under conditions wherein the catalyst catalyzes a reaction of the reactants to form products.

[019] In embodiments the reactants/products comprise methane/methanol, carbon

dioxide/carbonic acid or alcohol/aldehyde.

[020] The invention encompasses all combination of the particular embodiments recited herein, as if each combination had been laboriously recited.

[021] Brief Description of the Drawings

[022] Figures la-c, Design and synthesis of the catalysts bearing copper-oxygen complexes in MOF-808 for methane oxidation to methanol, a, Structure of MOF-808. b, Pseudohexagonal pore opening of MOF-808. c, Synthesis of the catalysts comprising the replacement of formate with imidazole-containing ligands and meta!ation with Cu(I). Atom labeling scheme: C, black; O, red; N, green; Cu, orange; Zr, blue polyhedra. H atoms are omitted for clarity. Orange spheres represent the space in the tetrahedral cages.

[023] Figures 2a-d: a, Average with standard error of methanol productivity of MOF-808- His-Cu, MOF-808-Iza-Cu and MOF-808-Bzz-Cu. b, Ex-situ N K-edge XANES spectra of MOF-808-Bzz, as-synthesized MOF-808-Bzz-Cu and MOF-808-Bzz-Cu after the reactions with Fie, 3% N₂0/He, CH₄ and 3% steam/TIe. c, Ex-situ Cu K-edge XANES spectra ofMOF-808- Bzz-Cu after the reactions with He, 3%N₂0/He, C¾ and 3% steam/He. d, Resonance Raman spectra of MOF-80S-Bzz-Cu synthesized using ⁱ⁶0₂ and ¹⁸G₂ with 407 ran laser. Note that ⁱ⁸G₂ spectrum contain some ¹⁶0₂ contamination.

[024] Figure 3, DFT optimized structure of the proposed active site in MOF-808-Bzz-Cu. From ICP, ¹ H NMR, and N K-edge XANES, each N atoms of the ligands is coordinated to one copper atoms. However, copper in bis(/i--oxo) dicopper is known to be four-coordinated '. We propose that the fourth ligand coordinating to copper is a neutral ligand such as water or NN- dimethyiformamide molecules as we observed the latter molecule in the ^! H NMR spectra of the digested samples after activation (only the optimized structure of the active site is shown, while the remaining atoms of the MOF-808 are omitted for clarity). Atom labeling scheme: C, black; O, red; N, green; H, white; Cu, orange.

[§25] Figures 4a-h, The series of ^-weighted Cu-EXAFS spectra of MOF-808-Bzz-Cu

(black line) and best fit (red line) in k-space (left) and //--space (right) without phase correction after the reactions with a,b He; c,d 3% N₂0/He; e,f CEL* and g,h 3% steam/He at 150 °C. Fitting was conducted using N scatter. Fit range: 3 < * < 10 A^-1; l < i? < 4 A; Fit window: Fiannmg

[026] Figure 5a-5b. SEM images of (a) MOF-808-His and (b) MOF-808-His-Cu.

[027] Figure 6. Elemental mapping using energy-dispersive X-ray spectroscopy of MOF-808- His-Cu shows uniform distribution of nitrogen and copper.

[02S] Figure 7a-7b, SEM images of (a) MOF-808-Iza and (b) MOF-808-Iza-Cu.

[029] Figure 8. Elemental mapping using energy-dispersive X-ray spectroscopy of MOF-808- Iza-Cu shows uniform distribution of nitrogen and copper.

[030] Figure 9a-b. SEM images of (a) MOF-808-Bzz and (b) MOF-808-Bzz-Cu.

[031] Figure 10. Elemental mapping using energy-dispersive X-ray spectroscopy ofMOF- 808-Bzz-Cu shows uniform distribution of nitrogen and copper.

[032] Figure 11. Partial structure of MOF-808-His resolved from single-crystal structure. Thermal ellipsoids are plotted with 50% probability.

[033] Figure 12. Partial structure of MOF-808-lza resolved from single-crystal structure. Thermal ellipsoids are plotted with 50% probability.

[034] Figure 13. Partial structure of MOF-808-Bzz resolved from single-crystal structure. Thermal ellipsoids are plotted with 50% probability.

[035] Figure 14. DFT optimized structure of MOF-808-Bzz-Cu. Selected geometric parameters (A): Cu-Ol = 1.784, Cu-G2 = 1 790, Cu-G3 = 1.938, Cu-N = 1.901 and Cu-Cu = 2.812. Atom labeling scheme: C, black; O, red; N, green; H, white; Cu, orange. [036] Figure 15. DFT optimized structure of MOF-808-Iza-Cu. Selected geometric parameters (A): Cu-Ol = 1.783, Cu-02 = 1.791, Cu-03 = 1.940, Cu-N = 1.898 and Cu- -Cu = 2.813. Atom labeling scheme: C, black; O, red; N, green; H, white; Cu, orange.

[037] Figure 16. DFT optimized structure of MOF-808-His-Cu. Selected geometric parameters (A): Cu-Ol = 1.781, Cu-02 = 1.801, Cu-03 = 1.957, Cu-N = 1.927 and Cu- - -Cu =^: 2.855. Atom labeling scheme: C, black; O, red; N, green; H, white; Cu, orange.

[038] Figure 17. DFT calculated Raman shift of Cu₂0₂ models. The reported Raman shifts are multiplied by 0.966 following the vibrational scaling factor. ⁿ

[039] Description of Particular Embodiments of the Invention

[040] Unless contraindicated or noted otherwise, in these descriptions and throughout this specification, the terms“a” and“an” mean one or more, the term“or” means and/or. It is understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims. All publications, patents, and patent applications cited herein, including citations therein, are hereby incorporated by reference in their entirety for all purposes.

[041] Bioinspired metal-organie framework catalysts for selective methane oxidation to methanol: Synthesis of the catalysts

[042] MOF-808 is composed of 12-connected cuboctahedron Zr₆0₄(0H)₄(-C00)i₂ secondary building units (SBUs) linked to the other SBUs by six benzenetricarboxylates (BTC) with three above and three below the ring of formates to form tetrahedral cages (Fig. la). When linked, these cages form an adamantane-shaped pore with formate, water and hydroxide molecules completing the coordination spheres of Zr(IV) and pointing into the pseudohexagonal pore openings (Fig. lb). Replacement of these formate, water or hydroxide molecules with imidazole- based ligands bearing carboxylic acid functionality will result in imidazole units localizing in the center of the pores. These ligands are spatially and precisely positioned for stabilizing copper- oxygen species in the framework (Fig. lc).

[043] Specifically, we synthesized microcrystalline MGF-808 to allow for a facile diffusion of substrates during post-synthetic modifications and catalysis . We selected three different metal binding ligands comprising biologically relevant imidazole units for incorporation into the framework to demonstrate the modularity of our system and to study the effect of how ligand rigidity influences the catalytic properties. Metal binding ligands including L-histidine (His), 4- imidazoleacryiic acid (Iza) and 5-benzimidazolecarboxylic acid (Bzz) were incorporated into the framework by heating MOF-808 in saturated solutions of these metal binding ligands to produce MOF-808-L with -L being -His, -Iza and -Bzz, respectively. The successful substitution of formate with these ligands in the MOF was confirmed by *H nuclear magnetic resonance (NMR) of the digested samples (Supplementary Section 2.1). Of the six available sites per chemical formula, approximately half of these were exchanged with the metal binding ligands to produce MOF-808-His [Zr₆0₄(0H)4(BTC)2(ffis)3.5(0H)_2.5(H₂0)2.5], MOF-808-Iza [Zr₆0₄(0H)₄(BTC)2 (Iza)_3.7(HCOO) i _.6(OH)_0.7(1¾0)_O.7] and MOF-808-Bzz [Zr₆0₄(0H)₄(BTC)₂(Bzz)_3.4(HC00) i ₆ (OH) s (H2O) ] . Similar procedures were performed on single crystals of MOF-808 for structural elucidation of these functionalized MOFs. Single crystal X-ray diffraction (SXRD) analysis reveals that these ligands bind to the Zr clusters in a bridging fashion with carboxylate group coordinating to Zr(IV) (Supplementary Section 4) and thus placing imidazole units in the center of the pseudohexagonal window. Meta!ation of these MOFs with Cut in MeCN under air at room temperature provides the catalysts, namely MOF-808-His-Cu, MOF-808-Iza-Cu and

MOF-808-Bzz-Cu. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis performed on these catalysts indicates the Cu/Zr₆ molar ratios of 4.9, 6.0 and 7.1 for MOF-808-His-Cu, MOF-808-lza-Cu and MOF-808-Bzz-Cu, respectively (Table 1). A control experiment was performed by metalation of MOF-808 under similar condition. Negligible incorporation of copper was observed (Cu/Zr₆ molar ratio ^:::: 0.3) indicating the role of imidazole ligands in ligating to copper atoms. The phase purity and crystallinity of the materials after post synthetic modifications were preserved as confirmed by powder X-ray diffraction (PXRD) analysis (Supplementary Section 2.2). The porosity of these materials was verified by N₂ adsorption-desorption isotherm measurements at 77 K with BET surface area of 385, 580, and 580 m² g ^! for MOF-808-His-Cu, MOF-808-Iza-Cu, and MOF-808-Bzz-Cu, respectively (Supplementary'- Section 2.3).

[§44] Table 1. Summary of catalyst compositions.

Catalyst L/Zr* molar ratio Cu/Zr₆ molar ratio Cu/L molar ratio

MOF-808-His-Cu 3.5 4.9 1.4

MOF-808-Iza-Cu 3.7 6.0 1.6

MOF-808-Bzz-Cu 3.4 7.1 2.1

MOF-808-Cu 0.3

[045] Methane oxidation

[046] Methane oxidation was conducted with an isothermal series of treatments at 150 °C. First, 100 g of MOF-808-L-Cu catalyst was pretreated in He flow to remove residual solvents (i.e., MeCN and water) at temperatures starting from room temperature to 150 °C at a ramping rate of 3 °C min ¹. After a clean background was achieved by monitoring the signals from a gas chromatograph, the catalyst was treated with 3% N₂0/He for 2 h at 150 °C followed by purging the catalyst with He for 30 min. The catalyst was subsequently exposed to a flow of CFL for 1 h at 150 °C for methane activation. After He purge, water was introduced in the form of 3% steam in He at 150 °C to desorb methanol. As shown in Fig. 2a, the average methanol productivity corresponds to 31.7 ± 13.0, 61.8 ± 17.5 and 71.8 ± 23.4 pmol gMOF-sos-L-cu ¹ for MOF-808-His- Cu, MOF-808-Iza-Cu, and MOF-808-Bzz-Cu, respectively; indicating that the MOF-808-Bzz- Cu has the highest methanol productivity among three catalysts. In terms of the turnover numbers (methanol productivity per mole of copper), MOF-808-His-Cu exhibited lower activity which is more likely due to lower number of catalytically active copper-oxygen species (-43% lower turno ver number compared to MOF-808-Bzz-Cu), attributed to the flexibility of histidine ligand. Notably, only methanol and water were observed as products during methanol desorption at a temperature below or equal to 150 °C. This was confirmed by gas chromatographs equipped with flame ionization and thermal conductivity detectors and a mass analyzer. Above this temperature, we observed increased methanol production with temperature, as we expected due to improved methanol extraction efficiency. However, C0₂ was also observed as a byproduct from the overoxidation of the methanol generated. For the control experiments, we did not observe any products in the experiments performed on MOF-808-L and Cut (Cu(I) precursor.

[047] We examined the structural integrity of the catalysts after the reactions. The crystallinity of the catalysts was maintained as evidenced by PXRD. Interestingly, unlike molecular copper- oxygen complexes¹⁹, ligand hydroxylation was not observed from digested *H NMR of the catalysts even at 150 °C, highlighting the significantly enhanced stability imposed by covalent attachment of the complexes that are geometrically constrained in the MOF.

[048] We performed recyclability test on MOF-808-Bzz-Cu with an isothermal series of treatment at 150 °C. A drastic deactivation was observed in the second and third cycle giving 7.5 pmol g ¹ and 0.1 pmol g ¹ methanol productivity, respectively. After the third cycle, MOF-808- Bzz~Cu was subjected to a flow of He by increasing temperature from 150 °C to 250 °C at a ramping rate of 3 °C min ¹ and hold for 10 min. Desorbed water was observed during this He treatment until the temperature reaches 250 °C. We then proceeded with the isothermal series of treatment at 150 °C; the catalyst showed methanol productivity of 5.4 pmol g ¹ which is similar to the productivity obtained from the second cycle. This result indicates that the catalyst deactivation is due to water molecules strongly bound to the active site. We also performed the recyclability test of MOF-808-His-Cu. There is a 77% decrease in methanol productivity from 28 pmol g ³ in the first cycle to 6.3 pmol g ¹ in the second cycle. Unlike MOF-808-Bzz-Cu, the histidine-derived catalyst still exhibits methanol productivity in the third and fourth cycle with 17% and 12% decrease per cycle. Even though there is a recyclability problem in MOF-808-L- Cu catalysts, it is noteworthy that this catalyst shows the highest reported methanol productivity at 71.8 pmol g ^! with an isothermal series of treatments at 150 °C with high selectivity to methanol/ The modularity in our catalysts shows that the recyclability can be improved by varying the coordination sphere around the active sites.

[049] Identification of the active site in MOF-SOS-L-Cu

[050] To elucidate the identity of the active site of the catalysts, we synthesized single crystals of MOF-808-L-Cu catalysts following similar procedures employed for microcrystalline samples. However, the active sites of the catalysts are crystal!ographical!y disordered prohibiting an unambiguous structural characterization using SXRD analysis (Supplementary Section 4). We therefore employed element- and structure-specific techniques to determine the structures of the acti ve sites. Energy-dispersive X-ray spectroscopy (EDS) analysis of the catalysts shows a uniform distribution of Zr, N and Cu atoms throughout the crystals, thus precluding the localization of the active sites on the surface of the MOF crystals (Supplementary Section 2 5).

[051] We carried out N K-edge X-ray absorption near edge structure (XANES), Cu K-edge X- ray absorption spectroscopy (XAS), UV-Vis diffuse reflectance spectroscopy (DRS) and resonance Raman spectroscopy measurements on three MOF-808-L-Cu catalysts (detailed spectroscopic data can be found in Supplementary Information). These catalysts show similar trends in the spectroscopic features unless otherwise noted. We therefore use MOF-808-Bzz-Cu as a representative in the following discussion. Comparison of N K-edge XANES spectra of MOF-808-Bzz and MOF-808-Bzz-Cu provides insight into the location of copper in the MOF catalysts (Fig. 2b). Two absorption bands at 398.8 and 400.6 eV are observed, assignable to the 1 s --> p* transitions of the nitrogen atoms in C-NH-C and C-N=C of imidazole ring,

respectively⁴⁰. After the metaiation, two absorption peaks are shifted and changed in intensity, indicating that Cu atoms are coordinated to N atoms that are part of the imidazole units. Ex-situ N K-edge X ANES measurements of the samples after each step of the series of treatments show that two absorption bands remain similar. This indicates that the Cu atoms are coordinated to N atoms throughout the catalytic process.

[052] Ex-situ Cu K-edge XANES measurements were performed to probe the oxidation states of copper during catalysis (Fig. 2c). Four characteristic peaks located at 8979, 8984, 8989, and 8998 eV are observed. The pre-edge region is shown in the inset of Fig. 2c showing a weak absorption peak around 8979 eV corresponding to a dipole- forbidden Cu(II) Is— » 3d electronic transition.⁴¹ The shoulder peak at 8989 eV is attributable to Cu(II) Is— » 4p+ L shakedown transition^42,4 \ Cu(I) Is— > 4p+ L shakedown feature is observed at 8984 eV⁴⁴. These data indicates that the catalysts are composed of a mixture of Cu(I) and Cu(II) species. The He pretreatment at 150 °C resulted in a decrease in the white line intensity at 8998 eV along with an increase in the absorption peak intensity at 8984 eV showing that the majority of Cu(II) is reduced to Cu(I) by autoreduction.⁴³’⁴⁶ The spectrum recorded after 3% N₂0/He at 150 °C exhibits oxidation of Cu(I) to Cu(II), indicative of the formation of the active copper oxygen species. After the reaction with methane at 150 °C, the peak intensity of Cu(I) at 8984 eV increased while the white line intensity decreased indicating the reduction of Cu(II) to Cu(I). This reduction could be ascribed to either hemolytic cleavage C-H bond followed by direct radical rebound route⁴ ' or Lewis acid/base pair adsorption of methane where oxygen atoms of the active copper-oxygen species reacted with methane^7,48. After methanol desorption was performed by flowing 3% steam/He at 150 °C into the catalyst, the white line intensity increased accompanied by decreasing intensity of the peak of Cu(l) at 8984 eV. This redox behavior of copper observed from Cu K-edge XANES further proves that the copper active site in our catalysts participates in methane oxidation to methanol. MOF-808-Iza-Cu also shows distinctive changes in the oxidation state of copper following the same trend through the course of the catalytic process as described for MOF-808-Bzz-Cu. MOF-808-His-Cu shows minor intensity changes, consistent with the lower methanol productivity as previously described (Fig. 2a).

[1)53] To gain more information about the active copper-oxygen species, UV-Vis DRS was performed. Background subtracted UV-Vis DRS spectra of the as-synthesized samples show the absorption band centered at -400 ran After 3% N₂G/He treatment at 150 °C, we observed the increase of this absorption band (Supplementary Section 5.1) corresponding to oxygen-to-metal charge-transfer transition^49-52. To definitively characterize this copper-oxygen species, we turned to resonance Raman spectroscopy measurement because each copper-oxygen species have characteristic Raman shifts ^16,1 ' (Supplementary Section 8). We prepared the samples by synthesizing MOF-808-L-Cu in an argon-fii led glovebox and oxygenating the samples with either ¹⁶0₂ or ⁱ⁸0₂ gas at room temperature. Figure 2d shows the isotope-dependent Raman peaks at -560 and -640 cm ¹ by using an excitation wavelength of 407 nm which is resonant at the charge-transfer band. These peaks are assigned to Cu- -O bonds vibration in the core breathing mode of bis(/ oxo) dicopper species (Supplementary Information, Section S6) In the 0₂-labeled samples, these Raman peaks are shifted to -545 cm and -630 cm

. This isotope- dependent trend is verified for all three MOF-808-L-Cu (Fig. 2d). Ex-situ resonance Raman spectroscopy of the samples after the treatments in He and 3% N₂0/He display similar Raman peaks, indicating that bis(/i-oxo) dicopper species are preserved prior to the methane activation. The deviation (-20 cm ¹) in the vibrational energy from the reported values¹ ' can be ascribed to the variation in the geometric parameters of the dicopper species due to the framework constraints.

[§54] With the information of the location of the ligands (Supplementary Section 4) and the identity of active copper-oxygen sites, we modeled the active sites using the framework as a constraint and geometrically optimized the models using density functional theory (DFT) calculations. Following the digested 1H NMR data where ~3 ligand molecules were incorporated per chemical formula, these ligands were placed on the Zr cluster on the pseudohexagonal window in a way such that these ligands pose a minimal steric hindrance to each other. Cu atoms were then allowed to coordinate to N atoms of imidazole units, and the Cu atoms were further coordinated to 0₂ to form N-Cu₂0₂-N species (Supplementary Section 6). Geometrical optimization indicates that bis( i-oxo) dicopper species can reside in the framework in all MOF- 808-L-Cu structures (Fig. 3). Of particular note, the Raman shifts relevant to 0₂ are in close agreement with the experimental data confirming the presence of bis(t-oxo) dicopper species in the catalysts (Supplementary Section 6).

[§§§] Fig. 4 depicts the k -weighted and Fourier transforms without phase correction of the extended X-ray absorption fine structure (EXAFS) data measured at the Cu K-edge of the MOF- 808-Bzz-Cu. The spectra were recorded after the successive treatment with (a) He, (b) 3%

N₂0/He, (c) CH₄ and, (d) 3% steam/He at 150 °C. We used the DFT-optimized cluster as a model to fit the experimental Cu EXAFS spectra. The full EXAFS data were analyzed in k- and i?-space using a combined k^l~k ²-k³ fitting procedure for reliable analysis⁵³. The best fits are presented in the figures and the respective fitted parameters are reported in Table 2. In the He treated sample, the first shell is assigned to Cu-N/(0) coordination with the coordination number of 2.9 at distance of 1.94 A. It should be noted that N and O atoms are indistinguishable fro EXAFS analysis as they have similar atomic scattering factors. For the second shell, we identified the scatterer by fitting the EXAFS data with Cu, C, N and O and only Cu could be fitted with reasonable fitting statistics. Copper was found at distance of 2.51 A with the coordination number of 0.6. This result indicates that copper site is present as dinuclear and a short distance of Cu Cu supports the presence of bis(/i-oxo) dicopper species. Contrary to a formal Cu(III) oxidation state typically assigned for bis( /-oxo) dicopper species^54,55, the oxidation state of active copper in our catalysts appears to be Cu(II). This discrepancy can be ascribed to the high electron density provided by the imidazole ligand to the Cu centers. The bond valence sum analysis (Supplementary Tables 5-7) further indicates the actual charge being close to 2-fold⁴⁴’⁵⁶’⁵⁷. Oxidation of the catalyst in 3% N₂0/He at 150 °C leads to 0.8 increase of the Cu-N/(0) coordination while its distance remains at 1.94 A indicating the additional formation of bis( /-oxo) dicopper species. After methane treatment, there is a slight decrease in Cu-N/(0) coordination and after methanol extraction, Cu-N/(0) coordination increases by 0.6. However, Cu-N/(0) coordination in MOF-808-His-Cu and MOF-808-Iza-Cu remains similar after treatment with methane and steam.

[056] Table 2. Cu EXAFS fitting result of MOF-808-Bzz-Cu with a series of treatments.

Ab-Sc pair N

R-factor

MOF-808-Bzz-Cu, He treated at 150 °C

Cu-N/(0) SS^f 2,9 ¹ · 94+0^, 02 0.0080+0.0025

0.019

Cu-Cu SS 0.6 2^,51+0.04 0.0146+0.0065

MOF-808-Bzz- Cu, N₂0 treated at 150 °C

Cu-N/(0) SS 3.7 1.94+0.02 0.0070+0.0025

0.021

Cu— Cu SS 0.4 2^,49+0.10 0.0156+0.0149

MOF-808-Bzz-Cu, CH4 treated at 150 °C

Cu-N/(0) SS 3.3 1.94+0.02 0.0072+0.0025

0.020

Cu— Cu SS 0.5 2^,51+0.07 0.0151+0.0102

MOF-808-Bzz-Cu, Steam treated at 150 °C

Cu-N/(0) SS 3.9 1.95+0.01 0.0058+0.0022

0.018

Cu-Cu SS 0.5 2.53+0.10 0.0169+0.0151

“Ab = absorber; Sc = scatterer. ^b Coordination number. ^' Distance (A).“ Debye- Waller factor (A"). ^eA measure of mean square sum of the misfit at each data point. -^f SS = single scattering; Fitting was conducted using N scatter. Fit range: .3 < k < 10 A ¹; 1 < R < 4 A; Fit window: Hanning.

[057] Methods

[058] Further details are available in the appended Supplementary Information.

[059] Synthesis of MOF-8O8. MOF-808 was synthesized following the reported procedure^·58. In a 100-mL media bottle, 1,3,5-benzenetricarboxylic acid (210 mg) and Zr0Cl₂-8H₂0 (970 g) were dissolved in a solution containing DMF (30 mL) and formic acid (30 mL). The bottle was sealed and heated in a 100 °C isothermal oven for a day. White powder was collected by centrifugation (8,000 rpm, 3 min), washed with DMF 3 times (60 mL x 3) over a 24 h period and with acetone 3 times (60 mL x 3) over a 24 h period. Finally, MQF-808 was dried under dynamic vacuum overnight at room temperature. EA of activated sample: Calcd for Zr₆O₄iOH)₄(C₉H₃O₆)₂iHCOO)₅(H₂O)(OH) (C₃H₇NO)_0.5: C, 21.17; H, 1.56; N, 0.50; Found: C,

21.18; H, 1.37; N, 0.44.

[060] Synthesis of MOF-8©8-Bzz. A solution of 5-benzimidazolecarboxylic acid was prepared by dissolving 5-benzimidazolecarboxylic acid (3 g) in DMSO (100 ml.) in a 250 mL bottle in a 100 °C isothermal oven. MO F- 808 (0.5 g) was suspended by sonication in the solution of 5-benzimidazolecarboxylic acid and the suspension was heated in a 100 °C isothermal oven overnight. The reaction was allowed to cool to room temperature. Brown powder was collected by centrifugation (8,000 rpm, 3 min), washed with DMSO 5 times (80 mL x 5) over 3 days and with acetone 5 times (80 mL x 5) over 3 days. Finally, MOF-8Q8~Bzz was dried under dynamic vacuum overnight at room temperature. LA of activated sample: Calcd for Zr₆0₄(0H)₄(C₉H₃0₆)₂(C₈H₅N₂0₂)_3.4(HC00)i_.6 (0H)i(H₂0)i: C, 32.15; H, 1.82; N, 5.45; O, 29.28; Zr, 31.30; Found: C, 31.07; H, 2.61; N, 5.30.

[061] Synthesis of MOF~S§8-Bzz~Cu. A solution of Cul (99.999% metals basis, 81.6 mg) in ACN (12.8 mL) was added to a suspension of MOF-808-Bzz (75 mg) in ACN (1.9 mL) in a 20 mL vial while stirring (500 rpm) under ambient conditions. The vial was sealed and the mixture was stirred for 3 days at room temperature. Brown powder was collected by centrifugation (8,000 rpm, 3 min) and washed with ACN 5 times (15 mL x 5) over 3 days. Finally, MOF-808- Bzz-Cu was dried under dynamic vacuum overnight at room temperature. I CP analysis: Cu/Zr molar ratio = 1.2.

[062] Catalysis. The catalytic testing was performed using a custom-designed continuous flow tubular reactor (Parr Instrument Co.). Mass flow controllers were calibrated using ADM 1000 flow meter (Agilent Technologies) and ultrahigh purity Fie, CH₄ (Research 5.0 Grade, Airgas), and 3% N₂0/He (Primary Standard Grade, Praxair) were flowed into a 30 cm long quarter inch 316-stainless steel reactor. The catalyst (100 mg) was sieved to 100-250 pm and placed in the middle of the reactor tube, delimited by a layer of purified glass wool and a layer of quartz sand (50-70 mesh) at each end. Pretreatment of the catalyst was conducted under He (30 seem) at 150 °C (3 °C/min) for 1 h. The catalyst was then oxidized using 3% N₂0/He flow (30 seem) at 150 °C for 2 h. After purging with He (30 seem) for 30 min, CH₄ (30 seem) was flowed into the catalyst for 1 h. After purging with He (50 seem) for 1 h, 3% steam/He (30 see ) was flowed into the catalyst. All lines were heated at 120 °C to prevent condensation. The outlet of the reactor was analyzed by gas chromatography (Model: GC-2014, Shimadzu Co.). The measurement started 3 min after opening the valve to 3% steam/He. The reactants and products were separated using HayeSep R 80/100 stainless steel packed column (12 ft, 1/8 in OD, 2mm ID) The water and C0₂ were monitored using a thermal conductivity detector and methanol was monitored using a flame ionization detector

[063] X-ray absorption spectroscopy (XAS). N K-edge X-ray absorption spectra were collected at beamline 8 0.1, an undulator beamline with energy range of 80-1200 eV of the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory (LBNL). Its spherical gratings monochromator delivers 1012 photons/second with linear polarization with a resolving power up to 6000. The experimental energy resolution is better than 0.15 eV. Experiments were performed at room temperature. All the spectra were collected in both total-electron-yield (TEY) and total-fluorescence-yield (TFY) modes simultaneou ly, corresponding to a probe depth of about 10 nm and 100 nm, respectively. We present spectra of TFY modes in this work as bulk measurement is preferred in our sample. The MOF-808-L-Cu samples were cooled down with a He purge after each gas treatment in a 316-stainless steel reactor. The reactor containing the sample was sealed with a Swagelok valve and moved to an argon- filled glovebox (H₂0 and 0₂ levels <1 ppm). The sample was unloaded and pressed onto an indium foil using a hand press. Thereafter these samples were transferred into an ultrahigh vacuum XAS end station (10 ⁹ torr) through our dedicated sample transfer kit to avoid air exposure. Energies were aligned by periodically collecting Ti L-edge spectra of a Ti0₂ (anatase) reference for N K-edge. The XAS spectra were recorded over a wide energy range covering energies well below and above sample absorptions. The normalization was performed following the established procedure: 1) I₀- normaiization: the sample signal is divided by the incident intensity measured from the sample drain current from a freshly coated gold mesh inserted into the beam path before the X-rays can impinge on the sample. 2) A linear, sloping background is removed by fitting a line to the fiat low energy region of the XAS spectrum, i.e., at energies below any absorption peaks 3) The spectrum is normalized by setting the flat low energy region to zero and the post edge to unity (unit edge jump).

[064] Cu K-edge X-ray absorption spectroscopy data were collected at the Advanced Light Source (ALS) bending-magnet beamline 10.3.2 (2.1-17 keV) with the storage ring operating at 500 mA and 1.9 GeV, using a Si(l 11) monochromator and adjustable pre-monochromator slits All data were collected at room temperature (24 °C) in fluorescence mode at the Cu K- edge (8980.48 eV). The incoming X-ray intensity ([<>) was measured in an ion chamber and the fluorescence emission with a seven element LN₂ cooled Ge solid state detector (Canberra) using XI A electronics. A Cu foil was used to calibrate the monochromator, with 1^st derivative maximum set at 8980.48 eV⁵⁹ and an internal IQ glitch (present in all spectra) was used to calibrate the data. The MOF-808-L-Cu samples were cooled down with a He purge after each gas treatment in a 316-stainless steel reactor. The reactor containing the sample was sealed with a Swagelok valve and moved to an argon-filled glovebox (H₂0 and 0₂ levels <1 ppm). The sample was unloaded and sealed with Kapton tape for ex-situ measurements. Cu K-edge

XANES spectra were recorded in fluorescence mode by continuously scanning the Si (111) monochromator (Quick XAS mode) from 8,880 to 9,020 eV, with 0.3 eV steps in the XANES region. All data were processed using the Lab VIEW^" custom BL 10.3.2 software to perform dead time correction, energy calibration, and glitch removal with detail procedure described elsewhere⁶⁰. XANES spectra were processed with Athena software⁶¹ to find first derivative peak (E₀), pre-edge background substruction and post-edge normalization, align and merge the spectra. EXAFS spectra were recorded up to 565 eV above the edge (8,880-9,545 eV, i.e , up to k ~ 12 A ¹) and 11 scans were averaged. EXAFS spectra of samples were reduced with k¹-, A²-, and A:³ -weighting, out to k ^:= 10 A^-1, and analyzed via shell -by-shell fitting using the FEFF61 code and the Artemi s software where it yields minima in variances ’ .

[065] Resonance Raman spectroscopy. In an argon-filled glovebox, a solution of Cut (6.25 mg) dissolved in anhydrous ACN (0.98 niL) was added to a suspension of MOF-808-Bzz (5.77 mg) in anhydrous ACN (0.14 mL) in a 1.5-mL GC autosampler vial equipped with a

PTFE/rubber septum. The vial was sealed and removed from the glovebox. Either ¹⁶0₂ (Praxair, 99.999%) or 0₂ (Aldrich, 99 atom %) was bubbled through the solution using a needle pierced through the septum at a rate of ca. 30 mL min ¹ for 10 min. The suspension was allowed to react at roo temperature for 3 days. The solid was collected by centrifugation, dried overnight, transferred to an Argon-filled glovebox and washed with anhydrous ACN 5 times (2 mL x 5) over 3 days. The sample was dried under dynamic vacuum overnight at room temperature, and the dried solid was transferred to the glovebox. The sample was loaded into a thin-wa!l quartz capillary'- tube and sealed with epoxy glue for the measurements. All spectra were collected using the 407 ran light with the power density of 3.1 W/cm . The Raman scattering was collected using a Spex 1401 double grating spectrograph and liquid nitrogen cooled Roper Scientific LN/CCD 1100 controlled by ST 133 controller. The measured Raman shifts were calibrated by using Raman peaks of cyclohexane.

[066] DFT calculations. The clusters were geometrically optimized at the density functional theory (DFT) in gas phase using spin-unrestricted B3LYP functional^63,64 as implemented in Gaussian 16 (revision A03) without symmetry constraints⁶⁵. The 6-31G basis sets were employed for C and H atoms while 6-31 lG(d) basis sets were used for Cu, N and O atoms. Numerical integrations were performed on an ultrafine grid. During geometry optimization, O atoms of carboxylate groups of the metal binding ligands were frozen to simulate the rigidity of the framework. Minima of all geometry-optimized structures were verified by having no imaginary frequency found from analytical frequency calculation performed at the same level of theory.

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[6133] Section SI. Synthesis of Materials

[0134] Post-synthetic Ligand exchange

[0135] MOF-808-His. A saturated solutio of 1-histidine was prepared by dissolving L~ histidine (93 mg) in water (8 mL) in a 20 mL vial in an 85 °C isothermal oven. MGF-808 (160 mg) was suspended by sonication in the saturatio solution of L-histidine and the suspension was heated in an 85 °C isothermal oven overnight. The reaction was allowed to cool to about 50 °C while the supernatant was carefully removed prior to the recrystallization of L-histidine. White powder was collected by centrifugation (8,000 rpm, 3 min), washed 5 times with water (10 mL 5) over 3 days and with acetone 5 times (10 mL * 5) over 3 days. Finally, MOF-808- His was dried under dynamic vacuum overnight at room temperature. EA of activated sample: Calcd for Zr₆0₄(0H)4(C9H306)2 (0^^302)3^(0^2.5^20)2.5: C, 27.22; H, 2.67; N, 8.55;

Found: C, 28.03; H, 3.05; N, 8.27.

[0136] MOF-808-Iza. A solution of 4-imidazole acrylic acid was prepared by dissolving 4- imidazole acrylic acid (6 g) in DMSO (70 mL) in a 100-mL bottle in a 100 °C isothermal oven. MOF-8Q8 (1 g) was suspended by sonication in the solution of 4-imidazole acrylic acid and the suspension was heated in a 100 °C isothermal oven overnight. The reaction was allowed to cool to room temperature. White powder was collected by centrifugation (8,000 rpm, 3 min), washed with DMSO 5 times (80 mL x 5) over 3 days and with acetone (80 mL x 5) over 3 days. Finally, MOF-808-Iza was dried under dynamic vacuum overnight at room temperature. EA of activated sample: Calcd for Zr₆04(OH)4(C9H30₆)2(C₆H₅N202)3 7(HCOO)_{] 6}(OH)o.7(H20)o ₇: C, 29.58; H, 1.91; N, 6.11; Found: C, 27.92; H, 2.35; N, 5.40.

[0137] Post-synthetic Meta!ation

[6138] MOF-808-Hls-Cu. A solution of Cul (99.999% metals basis, 47.8 mg) in ACN (7.5 mL) was added to a suspension of MOF-808-His (75 mg) in ACN (1.9 mL) in a 20 mL vial while stirring (500 rpm) under ambient conditions. The vial was sealed and the mixture was stirred 3 for days at room temperature. Green powder was collected by centrifugation (8,000 rpm, 3 min) and washed with ACN 5 times (15 ml. x 5) over 3 days. Finally, MOF-808-His-Cu was dried under dynamic vacuum overnight at room temperature. 1CP analysis: Cu/Zr molar ratio = 0.8.

[0139] MOF-868-Iza-Ca. A solution of Cut (99.999% metals basis, 76.5 mg) in ACN (12 mL) was added to a suspension of MQF-S08-Iza (75 mg) in ACN (1.9 mL) in a 20 mL vial while stirring (500 rpm) under ambient conditions. The vial was sealed and the mixture was stirred for 3 days at room temperature. Green powder was collected by centrifugation (8,000 rpm, 3 min) and washed with ACN 5 times (15 mL x 5) over 3 days. Finally, MOF-808-Iza-Cu was dried under dynamic vacuum overnight at room temperature. ICP analysis: Cu/Zr molar ratio = 1.0.

[6Ϊ46] MQF-808-Cu (control), A solution of Cul (99.999% metals basis, 81.6 mg) in ACN (12.8 mL) was added to a suspension of MOF-808 (75 mg) in ACN (1.9 mL) in a 20 mL vial while stirring (500 rpm) under ambient conditions. The vial w^ras sealed and the mixture was stirred for 3 days at room temperature. Brown powder was collected by centrifugation (8,000 rpm, 3 min) and washed with ACN 5 times (15 mL x 5) over 3 days. Finally, MOF-808-Bzz-Cu was dried under dynamic vacuum overnight at room temperature. ICP analysis: Cu/Zr molar ratio ^::: 1.2.

[0141] Synthesis of single crystalline samples

[1)142] Single crystals of MOF-808, To reduce nueleation of MOF single-crystals on vial surface, the inner surface of glass vials was rinsed with Sigmacote¹⁸' siliconizing reagent, washed three times with acetone, and dried in a drying oven before use. Single crystals of MOF-808 was prepared fol lowing the reported procedure. ^¾ Zr0Cl₂-8H₂0 (0.032 g, 0.10 mmol) and IT, BTC (0.022 g, 0.10 mmol) were dissolved separately in 2 ml DMF, then both solutions were combined in a 20 mL scintillation vial and 4 ml formic acid was added. This mixture was then placed in a 100 °C isothermal oven for three days. The crystals were washed with DMF 5 times (10 mL x 5) over 3 days.

[0143] Single crystals of MOF-808-His. Approximately 5 mg of single crystals of MOF-808 was washed with DI FI₂0 5 times (2 mL x 5) in a 4 mL scintillation vial. After which, a saturated solution of L-histidine prepared by dissolving L-histidine (23.25 mg) in water (2 mL) was added to the crystals. This mixture w^ras heated in an 85 °C isothermal oven overnight. The reaction was allowed to cool to about 50 °C while the supernatant was carefully removed prior to recrystallization of L-histidine. The crystals were washed 5 times with water (2 mL x 5) over 3 days.

[§144] Single crystals of MOF-808-Iza, Approximately 5 mg of single crystals of MOF-808 was washed with DM G 5 times (2 mL x 5) in a 4 mL scintillation vial. After which, a saturated solution of dissolving 4-imidazoleacrylic acid prepared by dissolving 4-imidazo!eacrylic acid (171 mg) in DMSO (2 mL) was added to the crystals. This mixture was heated in a 100 °C isothermal oven overnight. The reaction was allowed to cool to room temperature. The crystals were washed 5 times with DMSO (2 mL x 5) over 3 days.

[§145] Single crystals of MOF-808-Bzz, Approximately 5 mg of single crystals of MOF-808 was washed with DMSO 5 times (2 mL x 5) in a 4 mL scintillation vial. After which, a saturated solution of 5-ben imidazoiecarboxylic acid prepared by dissolving S-benzimidazolecarboxylie acid (60 mg) in DMSO (2 mL) was added to the crystals. This mixture was heated in a 100 °C isothermal oven overnight. The reaction was allowed to cool to room temperature. The crystals were washed 5 times with DMSO (2 mL x 5) over 3 days.

[0146] Section S2. Materials Characterization

[§147] Section S2.1 Solution ^!H NMR of digested samples

[§148] Solution

NMR spectra of digested samples were acquired on a Bruker AVB-400 (400 MHz) spectrometer at 297-300 K Samples of MOFs (-5 mg) were digested and dissolved by sonication in a mixture of DMSO-cL (560 mί-), hydrofluoric acid 48% (20 pL) and D₂0 (20 pL). Samples of MOFs containing Cu (~5 mg) were digested and dissolved by sonication in a mixture of DMSG-rib (500 pL), hydrofluoric acid 48 wt. % (20 pL), deuterium chloride (50 pL) and D₂0 (20 pL). We note that the quantification in samples containing Cu can be inaccurate due to the paramagnetic nature of Cu(II).

[0149] Section S2.5 Scanning electron microscopy (SEM)

[0150] Scanning electron microscope (SEM) images were obtained using a Zeiss Gemini Ultra- 55 analytical scanning electron microscope. The samples were prepared by dispersing MOF samples in acetone by sonication and the samples were drop - caste d on a silicon wafer

[0151] Section S4. Single Crystal X-ray Diffraction Analyses

[0152] Single crystal X-ray diffraction data were collected using synchrotron radiation on beam!ine 11 3.1 (currently 12.2 1) at the Advanced Light Source (ALS) at Lawrence Berkeley National Lab (LBNL) Beamline 11 3.1. is equipped with a PHOTON- 11 CMOS detector operating in shutterless mode, and the radiation is monochromated using silicon (111).

[CI153] Single crystal samples were mounted on MiTeGen® kapton loops and placed in a 100(2) K nitrogen cold stream using a Cryostream system (OXFORD). The raw data were processed with the Bruker APEX3 software package.² The data were first integrated using the SAINT V8.37A and then corrected for absorption with SADABS 2016/2 routines. The structures were solved by intrinsic phasing (SF1ELXT-2014) and the refinement was done by full-matrix least squares on F (SHELXL-2014), using the 01ex2 software package.’

[0154] For each structure, the MOF backbone was first assigned and refined anisotropically. The refinement on the disordered p₃-() (02A/Ό2B, 03A/03B) and oxygen from coordinating ligand (04A/04B) was conducted according to the previous report.⁵ Then, electron density peaks were assigned from the framework outwards - in other words, form the coordinating carboxylate group to the ligand’s dangling‘tail⁵. Due to the flexibility of the binding ligands as well as the proximity to a very⁷ high symmetry site, their positions are largely disordered so that only part of the ligand in each case can be clearly assigned. After the refinement on position and occupancy reached to convergence, anisotropic refinement of the fragment of binding ligand was performed (SADI, RIGLJ, and FLAT were applied to restrain the ligand in MOF-8G8~Bzz). Lastly, hydrogen atoms were added into geometrically calculated positions.

[0155]

Table S2. Crystal data and structure refinement for MOF-8G8~His.

Empirical formula Cri_.nHo_.sCL_.TiZro_.s

F ormula wei ght 1 15.01 100

Crystal system cubic

Space group Fd-3m

a/A 35.

b/A 35.0494(9)

c/A 35.0494(9)

a/° 90

b/° 90

g/° 90

Volume/A⁰ 43057(3)

Z 192

pcaicg/Cm³ 0.852

m/mm^"1 1.096

F(000) 10548.0

Crystal size/mm³ 0.03 x 0.03 x 0.03

Radiation Synchrotron (l = 0.8856 A)

2Q range for data collection/⁰4.096 to 67.542

Index ranges -43 < h < 43, -43 < k < 43, -43 < 1 < A Reflections collected 141062

Independent reflections 2137 [R_int = 0.2439, R_sigma = 0.0440] Data/restraints/parameters 2137/0/72

Goodness-of-fit on F ^' 1.109

Final R indexes [1>=2s (I)] Rj = 0.0643, wR₂ = 0.1971

Final R indexes [all data] Rj = 0.0937, wR₂ = 0.2204

Largest diff. peak/hole / e A ³ 1.32/-0.70

and structure refinement for MOF- )8~Iza. Empirical formula C1.74 H_G.50_2.83Zro_.5

Formula weight 1 12.36

Temperature/K 100

Crystal system cubic

Space group Fd-3m a, /A 35.0104(14)

Volume/A³ 42913(5)

Z 192

pcakg/cm³ 0.835

m/mm ¹ 1.282

F(000) 10294.0

Crystal size/mm³ 0.03 x 0.03 x 0.03

Radiation Synchrotron (l = 0.9537 A)

2Q range for data collection/⁰5.178 to 73.35

lndex ranges -42 < h < 43,

43, -43 < 1 < 42

Reflections collected 90189

Independent reflections 2108 [R 0.1485. R sigma 0.0329]

Data/restraints/parameters 2108/15/82

Goodness-of-fit on F² 1.134

Final R indexes [1>=2s (I)] R; = 0.0533, wR₂ = 0.1729

Final R indexes [all data] R = 0.0606, wR₂ = 0.1813

Largest diff. peak/hole / e A ³ 1.12/-0.74

Table S4. Crystal data and structure refinement for MQF-808~Bzz. Empirical formula Ci 9Ho.550_2.77Zro_.5

Formula weight 113.34

100

Crystal system cubic

Space group Fd-3m

a/A 35.0221(15)

35.0221(15)

c/A 35.0221(15) 90

b/° 90

g/° 90

Volume/A³ 42956(6)

Z 192

pcaicg/cm³ 0.841

m/mm ¹ 1.281

F(000) 10393.0

Crystal size/mm³ 0.03 x 0.03 x 0.03

Radiation Synchrotron (l = 0.9538 A)

2Q range for data collection/⁰5.178 to 68.494

Index ranges -41 < h < 41, -41 < k < 41, -41 < 1 < 41

Reflections collected 110295

Independent reflections 1795 [I¾_nt ^:::: 0.1312, R_sigma ^:::: 0.0341 ]

Data/restraints/parameters 1795/ 105/ 110

Goodness-of-fit on F² 1.158

Final R indexes [1>=2s (I)] Ri = 0.0570, wR₂ = 0.2085

Final R indexes [all data] R_¾ = 0.0650, wR₂ = 0.2224

Largest diff. peak/hole / e A ³ 1.25/-1.61

[0158] Section S5. UV-Vis Diffuse Reflectance and Resonance Raman Spectroscopy

[0159] The UV-Vis diffuse reflectance spectroscopy (DRS) spectra of MOF-808-L, MOF-808- L-Cu and MOF-808-L-Cu were collected using Shimadzu model UV-2450 spectrometer equipped with an integrating sphere model ISR-2200. The MOF-808-L-Cu samples treated under 3% N₂0/He at 150 °C for 1 h in a 316 stainless steel reactor was cooled down with He purge and is closed with Swagelok valve, moved to an argon-filled glovebox, and transferred into the home-built stainless steel vacuum cell for UV-Vis diffuse reflectance experiments.⁶ To illustrate the effect of metalation with Cu in the presence of dioxygen and reaction with N₂0, the spectra of MOF-808-L-Cu and MOF-808-L-Cu were subtracted using their corresponding MOF- 808-L spectra.

[0160] Section S5.2 Resonance Raman spectroscopy

[0161] In an argon-filled glovebox, a solution of Cul dissolved in anhydrous ACN was added to a suspension of MOF-808-L in anhydrous ACN in a 1.5-mL GC autosampler vial equipped with a PTFE/rubber septum. Specific stoichiometries are described below. The vial was sealed and removed from the glovebox. Either ¹⁶0₂ (Praxair, 99.999%) or ⁱ⁸0₂ (Aldrich, 99 atom %) was bubbled through the solution using a needle pierced through the septum at a rate of ca. 30 mL min ¹ for 10 min. The suspension was allowed to react at room temperature for 3 days. The solid was collected by centrifugation, dried overnight, transferred to an Argon-filled glovebox and washed with anhydrous ACN 5 times (2 mL x 5) over 3 days. The sample was dried under dynamic vacuum overnight at room temperature, and the dried solid was transferred to the glovebox. The MOF-808-L-Cu samples in the 316 stainless steel reactor was cooled down with a He purge after each gas treatment and is closed with Swagelok valve, and moved to the argon- filled glovebox. The sample was loaded into a thin-wall quartz capillary tube and sealed with epoxy glue.

2

[0162] All spectra were collected using the 407 rim light with the power density of 3.1 W/cm The Raman scattering was collected using a Spex 1401 double grating spectrograph and liquid nitrogen cooled Roper Scientific LN/CCD 1100 controlled by ST 133 controller. The measured Raman shifts were calibrated by using Raman peaks of cyclohexane.

[0163] Section S6. Density Functional Theory Calculations

[0164] Single crystal structure of MOF-808 was used as a model and formate molecules were replaced with either L-histidine, 4-imidazoleacrylic acid or 5-benzimidazolecarboxylic acid. Cu atoms were allowed to coordinate to N atoms of metal binding ligand and dioxygen to form Cu- O complexes. We assumed that Cu is 4-coordinated as they are the most common among bisip- oxo) dicopper complexes. From H NMR analysis, we observed the resonance peaks of DMF but not that of acetonitrile which was used during the synthesis. Thus, the fourth neutral ligand is likely to be terminal water or DMF. We used water in our model for simplicity. To reduce computational cost, the Cu-0 complexes along with their metal binding ligands were extracted from the models and carboxylate groups of metal binding ligands were neutralized with protons. The clusters were geometrically optimized at the density functional theory⁷ (DFT) in gas phase using spin-unrestricted B3LYP functional as implemented in Gaussian 16 (revision A03) without symmetry constraints.¹⁰ The 6-31G basis sets were employed for C and H atoms while 6-31 lG(d) basis sets were used for Cu, N and O atoms. Numerical integrations were performed on an ultrafme grid. During geometry optimization, O atoms of carboxylate groups of the metal binding ligands were frozen to simulate the rigidity of the framew⁷ork. Minima of all geometry- optimized structures were verified by having no imaginary frequency found from analytical frequency calculation performed at the same level of theory.

[§165] XYZ coordinates for DFT structures

[§166] MOF-808-ffis-Cu O 15.3201 24.8040 14.0507 C 15.2267 18.8603 16.3261 N 18.4341 18.0459 24.7045 O 17.1267 17.7002 26.9338 N 14.5385 19.687 17.1347 H 18.6781 17.5599 23.8314 O 25.3683 13.9674 15.1931 C 14.5551 20.9307 16.5229 H 18.6245 17.4266 25.5110 O 16.1149 19.7500 26.6483 Cu 18.3125 13.6649 20.7531 N 23.8881 15.9676 15.9724 O 17.0920 24.4448 12.6232 O 19.3183 12.4649 19.9023 H 24.3407 15.7759 15.0621 O 25.8425 13.4728 17.3924 Cu 19.8069 13.2154 18.3623 H 24.4845 16.6441 16.4692 H 15.1039 25.5995 13.5214 Cu 18.4478 16.3835 13.7242 N 16.588 23.5188 15.9322 H 16.9881 17.8083 27.8975 O 17.5766 17.4717 14.8614 H 17.4553 24.0285 16.1516 H 26.2186 13.5438 14.9540 Cu 16.5045 18.4730 13.8170 H 16.449 22.7856 16.6401 C 16.4198 24.1525 13.5700 Cu 13.6635 19,2619 18.7870 O 18.0916 12.4858 22.2839 C 16.6517 18.7669 26.2254 O 14.9544 18.2706 19.5534 O 20.7576 11.5861 17.8405 C 25.1436 13.9400 16.5398 Cu 14.2805 17.7853 21.1513 O 19.1802 15.4778 12.1668 C 16.6198 22.9373 14,5115 O 13.0183 18.7741 20.3749 O 15.5143 19.2462 12.3162 C 23.7767 14.6431 16.7410 O 17.3824 17.3886 12.7092 O 13.1263 17.4845 22.7030 C 16.9498 18.4371 24.7402 O 18.7976 14.4451 19.2064 O 12.0638 20.2921 18.3843 C 16.3998 16.5432 22.9903 H 16.8323 19.3300 24.1250 H 17.2471 12.2759 22.7159 C 16.0464 17.2497 24.2763 H 16.0391 16.5099 25.0849 H 18.6552 1 1.6917 22.3080 C 15.2604 20.8329 15.3332 H 17.6077 22.5008 14.3591 H 18.9598 15.8575 11.2973 C 15.4581 21.9143 14.2992 H 23.6299 14.8876 17.7938 H 19.2731 14.5159 12.0668 C 21.2813 14.3741 15.9335 H 14.528 22.4885 14.2194 H 11.5575 20.2455 17.5564 C 22.6372 13.7494 16.1545 H 22.9937 13.3527 15.1971 H 11.4400 20.4346 19.1 187 N 15.7780 16.7290 21.7480 H 16.0877 15.7726 19.8501 H 20.5979 11.0968 17.0155 C 16.3451 15.8491 20.8943 H 17.9331 15.0253 23.5622 H 14.5443 19.2823 12,2577 N 17.2720 15.0888 21.5058 H 18.1533 14.9713 16.575 H 12.3342 18.0518 22,7410 C 17.3177 15.5175 22.8232 H 21.4105 15.3523 13.9314 H 20.8796 10.9355 18.5565 N 20.1608 14.2314 16.7634 H 15.4106 17.8186 16.5347 H 15.8597 19.0147 11,4343 C 19.1443 14.8846 16.1592 H 14.0107 21.7721 16.9262 H 12.8831 16.6077 23.0459 N 19.5237 15.4167 14.9828 H 15.0303 17.6532 24.224 H 19.0446 18.8689 24.8053 C 20.8658 15.1051 14.8310 H 15.6286 21.4729 13.3122 H 22.9656 16.3948 15.8156 N 15.6684 19.4967 15.2194 H 22,5572 12.8908 16.8286 H 15.8133 24.2025 15.9843

[§167] MOF -808-Iza-Cu

O 15.6790 23.9618 12.4297 N 21.8701 15.7316 17.0182 H 22.7135 13.6115 14.4166 O 13.2198 16.0569 24.7248 C 21.6437 17.0455 16.8494 H 19.2395 17.9586 20.8786 O 22.8456 11.1650 14.5702 N 21.7212 17.3929 15.5477 H 17.6653 14.4622 22.6392 O 12.7286 18.2878 24.4289 C 21.9917 16.2351 14.8451 H 21.4180 17.7324 17.6486 O 17.6041 23.2925 11.3568 N 18.3150 21.6771 16.3834 H 22.0740 16.2070 13.7698 O 22.7297 10.4798 16.7663 C 18.2719 21.331 1 17.6812 H 19.0475 20.7843 18.1920 H 15.4835 24.3939 11.5783 N 17.1252 21.7441 18.2607 H 15.4012 22.7720 17.4466 H 12.4209 16.0662 25.2829 C 16.3875 22.3699 17.2751 O 16.5922 19.6295 23.9416 H 23.1171 10.2428 14.4097 Cu 20.3625 15.0321 21.0584 O 15.8516 23.2844 20.2498 C 16.8797 23.3147 12.3395 O 20.5131 15.7485 19.4239 O 20.5097 13.9794 22.6816

C 13.4237 17 .3076 24.2120 Cu 21.9707 14.9491 18.7525 O 23.6883 14.0865 18.5077

C 22.6072 11 .3369 15.9052 Cu 21.5270 19.1460 14.8469 O 22.9461 18.9468 13.5387

C 17.2671 22 .6418 13.6061 O 21.2703 20.8411 14.3574 O 20.0538 23.1779 14.6640

C 22.2057 12 .7267 16.2434 Cu 19.8621 21.3637 15.3164 H 15.4469 23.5011 21.1058

C 14.6386 17 .3891 23.3608 Cu 16.6561 21.5263 20.0868 H 20.2856 14.2613 23.5810

C 16.8755 16 .5412 22.5999 O 16.3570 21.1944 21.8129 H 23.0973 19.6980 12.9418

C 15.6199 16 .4612 23.3269 Cu 16.8840 19.5060 22.0302 H 16.2374 20.4786 24.2549

C 17.1 100 22 .3326 16.0922 O 17 2362 19.8461 20.3054 H 16.1760 18.9000 24.4343

C 16.6997 22 .8777 14.8092 O 20.1438 19.6763 15.8533 H 23.9895 13 5396 19.2527

C 22.0817 15 .1838 15.7448 O 21 8393 14.281 1 20.3994 H 23.9152 13.6483 17.6683

C 22.3538 13 .7924 15.4264 H 14.6716 18.2973 22.7669 H 19.2761 23.7028 14.4034

N 17.4379 17 .6830 22.0114 H 15.4741 15.5475 23.8976 H 20.7703 23.3160 14.0218

C 18.5920 17 .3028 21.4374 H 18.0825 21.9377 13.4720 H 16.1260 24.0950 19.7956

N 18.8299 15 .9897 21.6383 H 21.7877 12.8089 17.2419 H 21.2146 13.3117 22.7060

C 17.7605 15 .5005 22.3623 H 15.8413 23.5436 14.8437 H 23.7588 18.4284 13.6353

[ )168] MOF-808-Bzz-Cu

O 22.8655 26.2385 18.3411 C 20.3271 15.4528 14.5929 H 15.6571 18.9748 23.9809

O 1 1.7898 17.9039 23.5902 C 20.5172 15.8187 13.2547 H 14.3835 14.9936 21.1696

O 17.8916 14.7089 10.4660 C 19.6005 15.3497 12.3263 H 12.6898 16.2820 22.4246

O 13.1 169 19.3225 24.8242 N 17.1816 15.7054 21.3392 H 23.6461 22.5298 16.9663

O 23.9866 25.1857 16 6293 C 18.1872 16.5038 21 7403 H 21.5209 23 1798 21.4869

O 16.6259 13.2810 1 1 7523 N 17.7787 17.4860 22.5666 H 22.2064 25 1022 20.0948

H 23.0978 27.0430 17 8426 N 21.9889 20.4752 20.5751 H 17.4279 13 5877 14.3108

H 1 1.0666 18.3715 24.0464 C 22.3776 19.5784 19.6509 H 21.3290 16 4677 12.9460

H 17.2861 14.4216 9.7585 N 22.9151 20.1524 18.5573 H 19.7085 15 6188 11.2857

C 23.3588 25.1449 17 6783 N 21.0629 15.7647 15.7389 O 18.1976 18 7985 25.0508

C 12.9888 18.4194 24.0092 C 20.4107 15.1962 16.7690 O 22.4028 21.3439 23.2337

C 17.5479 14.0757 1 1 6320 N 19.3245 14.5003 16.3815 O 25.1203 20 2030 16.7666

C 22.9918 23.9185 18 4718 Cu 17.2276 14.1960 20.1853 O 23.5254 15 8342 14.3515

C 18.5015 14.5320 12.7048 O 18.2369 14.8792 18.8742 O 17.9340 12.0273 16.5308

C 14.0868 17.6761 23 2947 Cu 18.2167 13.5997 17.6210 O 16.2179 13 0474 21.3762

C 15.4182 18.0913 23.3980 O 17.2788 12.8952 18.9648 H 17.5278 18.2113 25.4305

C 16.3858 17.3511 22.6965 Cu 22.6322 16.8365 15.7496 H 25.4991 20.9071 17.3127

C 16.0188 16.2264 21.9123 O 22.2054 17.9414 17.0919 H 17.3820 11.3049 16.8684

C 14.6823 15.8246 21.7986 Cu 23.5447 19.1308 17.0963 H 22.2832 21.4743 24.1871

C 13.7325 16.5557 22.4954 O 24.0013 17.9792 15.8129 H 23.1644 21.8400 22.9008

C 23.2212 22.6379 17.9588 Cu 18.9807 18.7575 23.2829 H 23.2249 15.0446 13.8789

C 22.8454 21.5421 18.7552 O 20.2711 19.8859 23.7761 H 24.4017 16.1177 14.0482

C 22.2534 21.7344 20.0308 Cu 21.1826 20.1854 22.2715 H 16.0081 12.1420 21.0997 22.0105 23.0187 20.5330 O 19.9391 18.9919 21.7879 H 15.8719 13.2373 22.2601 22.3865 24.0959 19.7453 H 22.2629 18.5118 19.7639 H 18.5801 19.3758 25.7298 18.2980 14 1779 14.0423 H 20.7149 15.2936 17.7993 H 25.7218 19.9592 16.0460 19.2269 14.6475 14.9872 H 19.2122 16.3815 21.4272 H 18.3822 11.7692 15.7122

[§169] Section S7. X-ray Absorption Spectroscopy (XAS)

[§170] N K-edge X-ray absorption spectra were collected at beamline 8.0.1, an undulator beamline with energy range of 80-1200 eV of the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory (LBNL). Its spherical gratings monochromator delivers 1012 photons/second with linear polarization with a resolving power isp to 6000. The experimental energy resolution is better than 0.15 eV. Experiments were performed at room temperature. All the spectra were collected in both total-electron-yield (TEY) and total- fluorescence-yield (TFY) modes simultaneously, corresponding to a probe depth of about 10 nrn and 100 nm, respectively. We present spectra of TFY modes in this work as bulk measurement is preferred in our sample. The MOF-808-L-Cu samples w¾re cooled down with a He purge after each gas treatment in a 316-stainless steel reactor. The reactor containing the sample was sealed with a Swagelok valve and moved to an argon- filled glovebox (FLO and 0₂ levels <1 ppm). The sample was unloaded and pressed onto an indium foil using a hand press. Thereafter these samples were transferred into an ultrahigh vacuum XAS end station with low 1 O ⁹ torr through our dedicated sample transfer kit to avoid air exposure. Energies are aligned by periodically collecting Ti L-edge spectra of a Ti0₂ (anatase) reference for N K-edge. The XAS spectra were recorded over a wide energy range covering energies well below and above sample absorptions. The normalization was performed following the established procedure: 1) I₀-normalization: the sample signal is divided by the incident intensity measured from the sample drain current from a freshly coated gold mesh inserted into the beam path before the X-rays can impinge on the sample. 2) A linear, sloping background is removed by fitting a line to the flat low energy region of the XAS spectrum, i.e., at energies below any absorption peaks. 3) The spectrum is normalized by setting the flat low energy region to zero and the post edge to unity (unit edge jump).

[0171] Cu K-edge X-ray absorption spectroscopy data were collected at the Advanced Light Source (ALS) bending-magnet beamline 10.3.2 (2.1 -17 keV) with the storage ring operating at 500 mA and 1.9 GeV, using a Si(l 1 1) monochromator and adjustable pre-monochromator slits.¹² All data were collected at room temperature (24 °C) in fluorescence mode at the Cu K-edge (8980.48 eV). The incoming X-ray intensity (I₀) was measured in an ion chamber and the fluorescence emission with a seven element LN₂ cooled Ge solid state detector (Canberra) using XIA electronics. A Cu foil was used to calibrate the monochromator, with 1 ^sl derivative maximum set at 8980.48 eVⁱ³ and an internal To glitch (present in all spectra) was used to calibrate the data. The MOF-808-L-Cu samples were cooled down with a He purge after each gas treatment in a 316- stainless steel reactor. The reactor containing the sample was sealed with a Swagelok valve and moved to an argon-filled glovebox (H₂0 and 0₂ levels <1 ppm). The sample was unloaded and sealed with Kapton tape for ex-situ measurement. Cu K-edge XANES spectra were recorded in fluorescence mode by continuously scanning the Si (11 1) monochromator (Quick XAS mode) from 8,880 to 9,020 eV, with 0.3 eV steps in the XANES region. All data were processed using the Lab VIEW custom BE 10.3.2 software to perform dead time correction, energy calibration, and glitch removal with detail procedure described elsewhere ¹⁴ XANES spectra were processed with Athena software¹⁵ to find first derivative peak (¾), pre-edge background substraetion and post-edge normalization, align and merge the spectra. EXAFS spectra were recorded up to 565 eV above the edge (8,880-9,545 eV, i.e , up to k~ 12 A ^!) and 1 1 scans were averaged. EXAFS spectra of samples were reduced with k¹-, k ^z~, and &³-weighting, out to k = 10 A^-1, and analyzed via shell-by-shell fitting using the FEFF61 code and the Artemis software where it yields minima in variances.^15,16

Cu--Cu SS 0.6 2 51+0.04 0.0146+0.0065 0.019

Cu-C SS 0 5 3.71+0.18 0.0041+0.0282

MOF-808-Bzz- Cu, N₂0 treated at 150 °C

Cu-N/(0) SS 3.7 1.94+0.02 0.0070+0.0025 2.04 2.23

Cu-_"Cu SS 0.4 2.49+0.10 0.0156+0.0149 0.021

Cu-C SS 0.3 3.57+0.66 0.01 15+0.1 153

MOF-808-Bzz-Cu, CH₄ treated at 150 °C

Cu-N/(0) SS 3 3 1.94+0.02 0.0072+0.0025 1.81 2.00

Cu-Cu SS 0.5 2.51+0.07 0.0151+0.0102

Cu-C SS 0.8 3.66+0.17 0.0072+0.0287

M OF -808-Bzz- Cu, Steam treated at 150 °C

Cu-N/(0) SS 3.9 1.95+0.01 0.0058+0.0022

Cu-Cu SS 0.5 2,53+0.10 0.0169+0.0151 0.018

Cu-C SS 0 7 3.71 +0.15 0.0015+0.0230

[0173] ^eAb = absorber; Sc = scatterer. ^b Coordination number. ^c Distance (A). ^d Debye-Wailer factor (A²). ^eA measure of mean square sum of the misfit at each data point+Bond Valence Sums; Calculated using r₀ value Cu(II)-N = 1.719 A. ^s Calculated using r₀ value Cu(III)-N = 1.753 A ^h SS = single scattering; Fitting w¾s conducted using N scatter. Fit range: 3 < k < 10 A ¹; 1 < R < 4 A; Fit window: Hanning. Cu EXAFS fitting result of MOF-808-lza-Cu with a series of treatments.

[0175] “Ab = absorber; Sc = scatterer. ⁰ Coordination number. ^c Distance (A).“ Debye-Wailer factor (A ). ^eA measure of mean square sum of the misfit at each data point. ⁷ Bond Valence Sums; Calculated using r₀ value Cu(Il)-N = 1.719 A. ^g Calculated using r₀ value Cu(lll)-N = 1.753 A. ^ SS = single scattering; Fitting was conducted using N scatter. Fit range: 3 < k < 10 A ¹; 1 < R < 4 A; Fit window: Hanning.

j l S7. Cu EXAFS fitting result of MOF-808-His-Cu with a series of treatments.

2.50± 0.02 0.00634 .0022 0.013

Cu-Cu SS 0.5

Cu-C SS 0.3 3 56+0.21 0.0055: .325 MOF-808-His- Cu, N2O treated at 150 °C

Cu-N/(0) SS _3-l 1.94+0.01 0.00824 Ό.0023 1.71 1.87

Cu-Cu SS 0.3 2.46+0.10 0.0 ! 594 Ό.0131 0.017

Cu-C SS 0 3.68+0.17 0.00424 Ό.0265

MOF-808~His- Cu, CH4 treated at 150 °C

Cu-N/(0) SS 3.0 1.94+0.01 0.00814 Ό.0024 U 1.81

Cu-Cu SS 0.2 2.43+0.16 0.01684 Ό.0219 0.019

Cu-C SS O.7 3.69+0.15 0.00574 _:0.0234 MOF -808-His- Cu, Steam treated at 150 °C

Cu-N/(0) SS 3. 1.94+0.02 0.00874 0.0026 1.71 1.87

Cu-Cu SS 0.2 2.48+0.09 0.00824 Ό.0115 0.020

Cu-C SS O.g 3.71+0.13 0.00564 0.0208

[0177] “Ab = absorber; Sc = scatterer. ⁰ Coordination number. ' Distance (A).“ Debye-Waller factor (A+. ^eA measure of mean square sum of the misfit at each data point.⁷ Bond Valence Sums; Calculated using r₀ value Cu(Il)-N = 1.719 A. ^g Calculated using r₀ value Cu(lll)-N = 1.753 A. ^h SS = single scattering; Fitting w¾s conducted using N scatter. Fit range: 3 < k < 10 A⁴; 1 < R < 4 A; Fit window: Planning.

[0178] Section SB Identification of the active site

[0179] Copper-oxygen complexes are known to display unique spectroscopic properties that can distinguish one from another, particularly with combined UV-vis spectroscopy and resonance Raman spectroscopy. We reproduced the spectroscopic data of known copper-oxygen complexes compiled by El well et ah, Mirica et ah, Peter et al. and Vanelderen et ai. below for ease of comparison '’¹⁷⁴⁹ From our UV-vis DRS spectroscopic data, we observed the absorption bands centered at 400 nm and 650 nm. The absorption bands below 350 nm is indiscernible due to the overlapping with the absorption band of MOF-808. From resonance Raman spectra excited at 407 nm, only oxygen-isotope-sensitive Raman peaks located at 560 and 640 cm ' were detected. With this information, there are two possible active sites: bis(«-oxo) and m-oco dicopper. To distinguish these two species, we carried out resonance Raman spectroscopic measurement using an excitation wavelength of 532 nm. We do not observe any oxygen-isotope-sensitive Raman peaks. We therefore assigned bis(/r-oxo) dicopper as our active site.

[§180] Table S8. Generally observed spectroscopic information of copper-oxygen complexes.

[§181] Section S9. References

[§182] 1 Furukawa, H. et al Water adsorption in porous metal-organic frameworks and related materials. J Am. Chem. Soc. 136, 4369-4381 (2014). [§183] 2 Bruker. APEX2. (Broker AXS Inc., Madison, Wisconsin, U.S.A. 2010).

[§184] 3 Sheldrick, (1 M. A short history of SHELX Acta Crystallogr. Sect. A: Found.

Crystallogr 64, 112-122 (2008).

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[§186] 5 Trickett, C A. et al Definitive molecular level characterization of defects in

UiO-66 crystals. Angew. Chem. Int. Ed. 54, 11162-11167 (2015).

[§1S7] 6 Blatter, F., Moreau, F. & Frei, PL. J. Phys. Chem. 98, 13403-13407 (1994).

[§188] 7 Mirica, L. M., Ottenwae!der, X. & Stack, T. D. P. Structure and spectroscopy of copper- dioxygen complexes. Chem. Rev. 104, 1013-1046 (2004).

[§189] 8 Becke, A. D. j. Chem. Phys. 98, 5648-5652 (1993).

[0190] 9 Lee, C., Yang, W. & Parr, R. G. Development of the Colle-Salvetti correlation- energy formula into a functional of the electron density. Phys. Rev. B 37, 785 (1988).

[§191] 10 Gaussian 16 Rev. A.03 (Wallingford, CT, 2016).

[§192] 11 NIST Computational Chemistry Comparison and Benchmark Database, NIST

Standard Reference Database Number 101. Release 17b, September 2015, Editor: Russell D. Johnson III. h tfp://ceebdb.m st. gov/

[§193] 12 Marcus, M. A. et al. Beamline 10.3. 2 at ALS: a hard X-ray microprobe for environmental and materials sciences. J. Synchrotron Radiat. 11, 239-247 (2004).

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(1996).

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Synchrotron Radiat. 8, 322-324 (2001).

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Claims

CLAIMS:

1. A composition comprising a metal-organic framework (MOF) catalyst comprising metalated azole ligands which form a reactive metal-oxygen complex within the MOF

2. The composition of claim 1 wherein the MOF is metalated with Cu, Fe or Zn.

3. The composition of claim 1 or 2 wherein the ligands are imidazole-, pyrazole- and/or triazole ligands, preferably imidazole ligands, preferably selected from L-histidine, 4-imidazoleacrylic acid and 5-benzimidazo!ecarboxylic acid.

4. The composition of claim 1, 2, or 3 wherein the MOF is selected from MOF-808,

Zr₆0₄(0H)₄(BTC)₂(HC00)₅ (H₂0)_l(0H)₁, BTC=benzenetricarboxylate], PCN-777

[Zr₆(Q)₄(QH) o(H_2Q)₆(TATB)₂, 4,4’,4”- -triazine-2,4,6-triyl-tribenzoate], M0F-545

[Zr₆0g(H₂0)g(TCPP-H₂)_2, TCPP-H₂=tetrakis(4-carboxyphenyl)porphyrin], NU-1000

[Zr₆0₄(0H)₄(0H)₄(0H₂)₄(TBAPy)₂, l,3,6,8-tetrakis( ?-benzoate)pyrene], PCN-133

[Zr₆0₄(0H)₄(BTB)₂(DCDPS)₃, BTB = l ,3,5-tris(4-carhoxyphenyl)benzene, DCDPS = 4,4’- dicarboxydiphenyl sulfone], PCN-134 [Zr₆0₄(0H)₆(H₂0)₂(BTB)₂(TCPP-H₂), BTB = 1,3,5- tris(4-carboxypheny!)benzene, TCPP-H₂ ^:::: tetrakis(4-carhoxyphenyl)porphyrin)], PCN-224 [Zr₆0₄(0H)₄(H₂0)₆(0H)₆(TCPP-H₂)i ₅, TCPP-H₂ = tetrakis(4-carboxyphenyl)porphyrin)] , MOF-802 [Zr₆0₄(0H)₄(PZDC)₅(HC00)₂(H₂0)₂, PZDC = ltf-pyrazole-3,5-dicarboxylate), MOF-841 [Zr₆0₄(0H)₄(MTB)₂(HC00)₄(H₂0)₄, MTB = 4,4’,4",4^m-methanetetrayltetrabenzoate] and DUT-67 [Zr₆0₄(0Fi)₂(TDC)₄(Cii₃C00)₄, TDC = thiophene-2, 5 -dicarboxyl ate]

5. The composition of claim 1, 2, 3 or 4 wherein the catalyst has catalytic activity selected from methane oxygenase, carbonic anhydrase and alcohol dehydrogenase

6. The composition of claim 1, 2, 3 or 4 wherein the catalyst has methane oxygenase activity, and the composition further comprises reactants or products of the activity, namely reactants: methane, N₂0, 0₂ and NAD(P)H and products: methanol, N_¾ water, and NAD(P)).

7. The composition of claim 1, 2, 3 or 4 wherein the catalyst has methane oxygenase activity, and the composition further comprises reactants and products of the activity, namely reactants: methane, N₂0, 0₂ and NAD(P)H and products: methanol, N₂, water, and NAD(P)).

8. The composition of claim 1, 2, 3 or 4 wherein the catalyst has carbonic anhydrase activity, and the composition further comprises reactants or products of the activity, namely reactants: carbon dioxide and water and product: carbonic acid.

9. The composition of claim 1, 2, 3 or 4 wherein the catalyst has carbonic anhydrase activity, and the composition further comprises reactants and products of the activity, namely reactants: carbon dioxide and water and product: carbonic acid.

10. The composition of claim 1, 2, 3 or 4 wherein the catalyst has alcohol dehydrogenase activity, and the composition further comprises reactants or products of the activity, namely reactant alcohol (e.g. ethanol) and NAD’ , and products: aldehyde (e.g. acetaldehyde) and

NADH.

11. The composition of claim 1, 2, 3 or 4 wherein the catalyst has alcohol dehydrogenase activity, and the composition further comprises reactants and products of the activity, namely reactant alcohol (e.g. ethanol) and NAD^" , and products: aldehyde (e.g. acetaldehyde) and NADH.

12. The composition of claim 1 wherein:

the MOF is metalated with Cu;

the ligands are selected from L-histidine, 4-imidazoleacrylic acid and 5- benzimidazolecarboxylic acid;

the MOF is MOF-808, Zr₆0₄(0H)₄(BTC)₂(HC00)₅ (H₂0)i(0H)i; and

the catalyst has catalytic activity that is methane oxygenase.

13. The composition of clai 1 wherein:

the MOF is metalated with Cu;

the ligands are selected from L-histidine, 4-imidazoleacrylic acid and 5- benzimidazoleearboxy!ic acid;

the MOF is MOF-808, Zr₆0₄(0H)₄(BTC)₂(HC00)₅ (H₂0)i(0H)_t; and

the catalyst has catalytic activity that is methane oxygenase, and the composition comprises reactants and products of the activity, namely reactants: methane, N₂0, 0₂, and NAD(P)H, and products: methanol, N₂, water, and NAD(P)).

14. A method of making the composition of claim 1 comprising metalating the ligands to incorporate reactive metal-oxygen complexes within the MOF.

15. A method of using the composition of claim 1 comprising forming a mixture of the catalyst and reactants under conditions wherein the catalyst catalyzes a reaction of the reactants to form products, wherein the reactants/products optionally comprise methane/methanol, carbon dioxide/carbonic acid or alcohol/aldehyde.