CN112452315B - Application of high-temperature sintering-resistant catalyst - Google Patents
Application of high-temperature sintering-resistant catalyst Download PDFInfo
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Abstract
The invention relates to the field of catalysts, and discloses an application of a high-temperature sintering-resistant catalyst, which can be used for catalyzing formic acid solution to prepare hydrogen, performing heterogeneous catalytic reaction, preparing hydrogen fuel cells, performing cathode corrosion resistance, preparing boride targets, preparing boride nozzle composite materials, preparing boride ceramic materials, preparing boride coatings, preparing boride surface coating film materials, preparing wear-resistant materials, preparing energy chemical engineering, preparing petrochemical engineering, activating hydrocarbon bonds, preparing medicaments and preparing hydrogen-containing water. The catalyst comprises transition metal nano particles and a metal boride carrier loaded with the transition metal nano particles; the transition metal nanoparticles are selected from group VIII and group IB transition metals; the chemical general formula of the metal boride carrier is M m B n Wherein M represents a metal. The transition metal nano particles and the transition metal boride carrier in the catalyst have strong metal-carrier interaction, so that the catalyst has excellent high-temperature sintering resistance.
Description
Technical Field
The invention relates to the field of catalysts, in particular to application of a high-temperature sintering-resistant catalyst.
Background
The metal nano catalyst (such as Pt, ag, pd, au and the like) has unique electronic structure and size effect, and the activity and the selectivity are far higher than those of the traditional catalyst, so that the metal nano catalyst has wide application prospect in the fields of petrochemical industry, fine chemical industry, environmental protection catalysis and the like. However, the nano catalyst has large specific surface area and high surface free energy, and irreversible sintering agglomeration phenomenon can occur under high-temperature reaction conditions, so that the activity of the nano catalyst is gradually reduced or even completely lost. In particular, many of the currently important industrial catalytic processes, such as heavy oil catalytic cracking, volatile Organic Compound (VOC) catalytic combustion, hydrocarbon reforming, automobile exhaust gas treatment, etc., often react at temperatures up to 600 f o Above C, the catalyst is extremely easy to sinter and deactivate rapidly, which greatly limits the practical application of the metal nano-catalyst in the fields. Therefore, developing a bifunctional metal nano catalytic system with high catalytic activity and high-temperature sintering resistance is a scientific front problem to be solved in the heterogeneous catalysis field all the time, and is also a key factor for breaking through in industrial application.
To achieve the above object, researchers have developed advanced technologies such as interface confinement, space confinement, nano-alloy, etc. successively. The classical Metal-carrier Strong interaction (Strong Metal-Support Interactions, SMSI) not only can effectively adjust the morphology and electronic properties of the Metal nano particles and greatly improve the activity and selectivity of the Metal nano particles, but also can improve the high-temperature stability of the catalyst through physical confinement, and is considered as one of the most effective methods for constructing the efficient anti-sintering Metal nano catalyst. For the construction of SMSI systems, the first requirement is to find a suitable support for the metal nanocatalyst.
Transition metal boride (Transitional Metal B)The orides, TMBs have very high melting points (as TiB) 2 And ZrB 2 For example, the melting points are respectively as high as 2980 o C and 3245 o C) And excellent chemical stability (TiB) 2 And ZrB 2 The antioxidation temperature in the air can respectively reach 1000 o C and 1300 o C) Is an unobtainable high temperature resistant material. Meanwhile, the transition metal boride is a typical two-dimensional lamellar material, has strong covalent bonding effect in a plane, is not limited by the lattice matching degree of the material, and can form interaction with other materials through Van der Waals force, so that the performances of photoelectricity, catalysis and the like of the material are greatly improved. Therefore, the transition metal boride is widely applied and mainly can be used for cathode corrosion prevention, target materials, nozzle composite materials, ceramic materials, coatings, surface coating film materials, wear-resistant materials and the like, but is rarely applied to catalysis research so far. In addition, the metal boride is prepared industrially at present mainly by a carbothermic reduction method or a direct element synthesis method, and the methods have the problems of low product purity, large granularity, high preparation cost and the like.
It is well known that hydrogen energy has the advantages of environmental protection, no toxicity and pollution, high heat value and the like, and is known as "energy currency" in new times, but the hydrogen has the problems of difficult storage, safe transportation and the like due to the characteristics of low boiling point, small density and quick diffusion. Therefore, the development of liquid hydrogen storage technology has a significant role in the effective utilization of future hydrogen energy. In recent years, the preparation of hydrogen from hydrogen-containing compounds such as formic acid/formate has been attracting attention, and formic acid has the advantages of no toxicity and stability at normal temperature, and has a hydrogen content of up to 4.4wt%, which is an excellent hydrogen storage material. Meanwhile, formic acid is a byproduct of preparing acetic acid by oxidizing light oil, and recycling the formic acid has very high application value for environment and industrial production, and formate can also be prepared by a simple carbon monoxide synthesis method. For formate decomposition to produce hydrogen, the decomposition products are bicarbonate and hydrogen. The process does not generate other gases and has no side reaction, so that pure hydrogen can be obtained, and the process is widely used in the field of fuel cells. However, heterogeneous catalysts currently catalyzing the decomposition of formic acid/formate generally rely on high loadings of Pd, which undoubtedly increases the cost of preparation; meanwhile, currently used catalysts for catalyzing formate decomposition are generally inactive at room temperature and must be heated to generate and release hydrogen. Therefore, by developing a novel heterogeneous catalyst, the realization of efficient catalysis of formic acid/formate decomposition to produce hydrogen at room temperature has become a focus of attention.
Disclosure of Invention
In order to solve the technical problems, the invention provides application of a high-temperature sintering-resistant catalyst, which can be used for catalyzing formic acid solution to prepare hydrogen, performing heterogeneous catalytic reaction, preparing hydrogen fuel cells, performing cathode corrosion prevention, preparing boride targets, preparing boride nozzle composite materials, preparing boride ceramic materials, preparing boride coatings, preparing boride surface coating film materials, preparing wear-resistant materials, preparing energy chemical industry, petrochemical industry, activating hydrocarbon bonds, preparing medicaments and preparing hydrogen-containing water.
The catalyst provided by the invention consists of transition metal nano particles and a transition metal boride carrier, and the transition metal nano particles and the transition metal boride carrier have strong metal-carrier interaction, so that the transition metal nano particles and the transition metal boride carrier can form a stable core-shell structure in the high-temperature treatment process, and the transition metal nano particles are ensured to have excellent sintering resistance.
The specific technical scheme of the invention is as follows:
in a first aspect, the present invention provides a high temperature sintering resistant catalyst comprising transition metal nanoparticles and a metal boride support supporting the transition metal nanoparticles; the transition metal nanoparticle comprises any one or more of group VIII and group IB transition metals; the chemical general formula of the metal boride carrier is M m B n Wherein M represents a metal, 0<m:n≤4。
The inventors have prepared nanoscale metal borides, such as TiB, using molten salt synthesis 2 And ZrB 2 And (3) an equivalent nanomaterial. When we supported nano transition metal oxides on metal borides, we unexpectedly found that there was a strong metal-support interaction between the two. This is the first time in the world that there is a strong metal-support interaction between transition metal and transition metal borideActing as a medicine. By strong metal-support interaction is meant that the metal is supported on a metal oxide support (typically a reducing support), which is partially reduced and transfers some electrons to the metal when reduced at high temperatures; at the same time, the carrier will partially migrate to the metal surface to form a special core-shell structure (metal is core, metal oxide is shell), resulting in metal-to-reactant (e.g. H 2 ) Is reduced or enhanced. However, in the present invention, the applicant has unexpectedly found that a similar metal-support strong interaction is also formed between the transition metal and the transition metal boride, which results in the transition metal nanoparticle and the transition metal boride support forming a stable core-shell structure during high temperature treatment, so that the transition metal nanoparticle has excellent high temperature sintering resistance, and can maintain the nanoparticle not agglomerated and uniformly dispersed through high temperature calcination above 500 ℃. At the same time, this effect also alters the catalytic activity of the transition metal or metal boride. In particular, the high temperature sintering resistant catalyst can be used for catalyzing the hydrogen production of formic acid/formate aqueous solution at room temperature.
Preferably, the mass ratio of the transition metal nano particles to the metal boride carrier is 0.01:100-20:100; further, the mass ratio of the transition metal nano particles to the metal boride carrier is 0.05:100-2:100; optimally, the mass ratio of transition metal nanoparticles to metal boride carriers is 1:100.
Preferably, the transition metal nano particles are metal simple substances or metal alloys; further, the metal simple substance is any one or more of Pt, cu, ag, au, co, rh, ir, fe, ru, ni and Pd; the metal alloy is Pt alloy; optimally, the metal simple substance is Pt; the metal alloy is PtCo alloy.
Preferably, the transition metal nanoparticles have a size of less than 50 nanometers; further, the size of the transition metal nano particles is 1-10 nanometers; optimally, the transition metal nanoparticles have a size of 2.5 nanometers.
Preferably, M is any one or more of Ti, zr, cr, hf and W; feeding inOne step, the metal boride carrier is TiB 2 、ZrB 2 、MgB 2 、Cr 2 B、HfB 2 And WB; optimally, the metal boride carrier is TiB 2 。
Preferably, the metal boride support is in the form of a shaped body of any size and geometry; further, the particle size of the metal boride carrier is 5-500 nanometers; the specific surface area of the metal boride carrier is 10-400 m 2 Per gram or 60-800 m 2 Per gram or 50-550 m 2 And/g. Optimally, the particle size of the metal boride carrier is 100 nanometers.
Preferably, the metal boride carrier is prepared by a molten salt synthesis method, a carbothermic reduction method, and a borothermic reduction method. Further, the metal boride carrier is prepared by a molten salt synthesis method, comprising: mixing and grinding nano metal oxide, boron powder, carbon powder, naCl and KCl, calcining at high temperature, washing with water, washing with alcohol, and drying.
Further, the preparation method of the metal boride carrier comprises the following steps:
taking nano metal oxide powder and boron powder as main reactants, and carbon powder as a reducing agent, wherein the molar ratio of the nano metal oxide to the boron powder to the carbon powder is 2:1:1-1:10:15; naCl and KCl are used as molten salt, and the mol ratio of NaCl to KCl is 1:0.5-2; the ratio of the total mass of the nano metal oxide to the total mass of the boron powder to the total mass of NaCl and KCl is 2:1-10; mixing and grinding the raw materials, placing the mixture into an alumina or platinum crucible, heating to 800-1600 ℃ under the protection of inert gas, keeping the temperature for 1-5 h at the temperature at the heating rate of 5-20 ℃/min, washing with water and ethanol after cooling to room temperature, removing impurities, and drying at 20-80 ℃ for 2-48 h to obtain the metal boride carrier.
The molten salt synthesis method is to use one or a plurality of low-melting salts as reaction medium, and the reactants have certain solubility in molten salt, so that the reaction is carried out in atomic level. After the reaction is finished, the salt is dissolved by adopting a proper solvent, and the synthetic product can be obtained after filtering and washing. As the low-melting-point salt is used as a reaction medium, a liquid phase appears in the synthesis process, and reactants have certain solubility in the liquid phase, so that the diffusion rate of ions is greatly accelerated, the reactants realize atomic scale mixing in the liquid phase, and the reaction is converted from solid-solid reaction to solid-liquid reaction. Compared with the conventional solid phase method, the method has the advantages of simple process, low synthesis temperature, short heat preservation time, uniform chemical components of the synthesized powder, good crystal morphology, high phase purity and the like. In addition, the salt is easy to separate and can be reused.
The molten salt synthesis method provided by the invention has the advantages of simple and convenient steps for preparing the nano transition metal boride, low equipment requirement, no need of using high-price raw materials such as titanium powder and the like, and obvious reduction of production cost. The product prepared by the method has high purity, less impurity residue and proper particle size, and can be applied to multiphase catalytic reaction, hydrogen production, hydrogen fuel cells, cathode corrosion prevention, boride targets, boride nozzle composite materials, boride ceramic materials, boride coatings, boride surface coating film materials, wear-resistant materials, energy chemical industry, petrochemical industry, hydrocarbon bond activation, pharmacy, preparation of hydrogen-containing water and other purposes.
Preferably, the nano metal oxide is TiO 2 、ZrO 2 、HfO 2 、WO 3 And Cr (V) 2 O 3 Any one or any plurality of the following; further preferred is TiO 2 。
Preferably, the carbon powder is any one or more of active carbon, graphite, carbon fiber and graphene; activated carbon is further preferred.
Preferably, the inert gas is nitrogen, argon or helium; argon is further preferred.
Preferably, the molar ratio of the nano metal oxide to the boron powder is 3:10, the weight ratio of the nano metal oxide to the carbon powder is 1:2, and the molar ratio of NaCl to KCl is 1:1;
preferably, the temperature is raised to 1000 ℃.
In a second aspect, the present invention provides a method for synthesizing two high temperature sintering resistant catalysts.
The first method comprises the following steps:
1) The transition metal nanoparticle and the metal boride carrier are prepared separately.
2) And (2) loading the transition metal nano particles prepared in the step (1) on the surface of a metal boride carrier or in the metal boride carrier to prepare a metal nano catalyst, then stabilizing the metal nano catalyst through heat treatment, and simultaneously removing ligands and pollutants on the surface of the transition metal nano particles to obtain the high-temperature sintering-resistant catalyst.
The second method comprises the following steps:
1) Preparing a metal boride carrier.
2) And (2) loading metal nano particles on the metal boride carrier material prepared in the step (1) by utilizing a transition metal precursor through an in-situ reduction method or other loading methods to prepare a metal nano catalyst, and then stabilizing the metal nano catalyst through heat treatment, and simultaneously removing ligands and pollutants on the surface of the transition metal nano particles to obtain the high-temperature sintering-resistant catalyst.
Preferably, the metal precursor is a nitrate, sulfate, chloride, oxalate, carbonate, citric acid, nitrate or a combination thereof of a transition metal. The selected reducing agents are sodium borohydride, borane and boroamine.
In a third aspect, the invention provides a specific application of the high temperature sintering resistant catalyst.
The high-temperature sintering-resistant catalyst has the performance of catalyzing the formic acid solution to prepare hydrogen.
The formic acid solution is formic acid or formate water solution, and the concentration of the formic acid solution is 1-22 mol/L; further, the concentration of the formic acid solution was 10mol/L.
The water molecules in the formic acid solution can change the adsorption configuration of formic acid on the surface of the catalyst, thereby playing a promoting role in the process of catalyzing the formic acid to prepare hydrogen.
Further, the catalytic hydrogen production reaction can decompose formic acid or formate solution to produce hydrogen without the need for external energy, but does not preclude the use of external energy to increase the reaction rate. The term "applied energy" includes, but is not limited to, any one or more of mechanical energy, thermal energy, electrical energy, optical energy, and ultrasound.
Although the catalytic hydrogen production reaction can be carried out at 0 ℃, the hydrogen production reaction temperature can be 0-100 ℃ in order to achieve the optimal hydrogen production efficiency; preferably, the reaction temperature of the catalytic system is 0-30 ℃; preferably, the reaction temperature of the catalytic system is room temperature; more preferably, the reaction temperature of the catalytic system is 0-10 ℃; more preferably, the reaction temperature of the catalytic system is 0 ℃. The room temperature may be a standard room temperature (23±5 ℃), or may be a real room temperature.
The hydrogen production reaction further comprises an auxiliary agent selected from sodium formate, ethylenediamine, triethylamine, KOH and Na 2 CO 3 、K 2 CO 3 Any one or any plurality of NaOH.
In addition, the high-temperature sintering-resistant catalyst provided by the invention can be applied to the fields of heterogeneous catalytic reaction, hydrogen fuel cells, cathode corrosion prevention, boride targets, boride nozzle composite materials, boride ceramic materials, boride coatings, boride surface coating film materials, wear-resistant materials, energy chemical industry, petrochemical industry, hydrocarbon bond activation, pharmacy, preparation of hydrogen-containing water and the like. Furthermore, the hydrogen prepared by the high-temperature sintering-resistant catalyst can be used as a high-quality fuel in the energy chemical and petrochemical processes. Furthermore, the high-temperature sintering-resistant catalyst can be used for cathode corrosion prevention, boride targets, boride nozzle composite materials, boride ceramic materials, boride coatings, boride surface coating film materials and wear-resistant materials. Further, the high temperature sintering resistant catalyst can be used in pharmaceutical and medical fields, such as preparing medical hydrogen-containing water.
Compared with the prior art, the invention has the beneficial effects that:
(1) The catalyst is composed of transition metal nano particles and a transition metal boride carrier, the invention discovers that the transition metal nano particles and the transition metal boride carrier have strong metal-carrier interaction for the first time, and the effect ensures that the loaded transition metal nano particles have excellent high-temperature sintering resistance, and can still keep the nano particles from agglomerating after high-temperature calcination at the temperature of more than 500 ℃.
(2) The transition metal boride carrier in the catalyst is prepared by a molten salt synthesis method, and nano transition metal boride with uniform size can be synthesized. The synthesis method has the advantages of simple steps, low equipment requirement, no need of using high-price raw materials such as titanium powder, obvious reduction of production cost, high purity of the prepared product, less impurity residues and proper particle size.
(3) The catalyst of the invention has high hydrogen production efficiency by catalyzing formic acid, can produce hydrogen at low temperature (more than or equal to 0 ℃), is an energy-saving hydrogen production system, has clean and environment-friendly catalysis process, and is suitable for industrial production.
(4) The invention proves that the water molecules can change the adsorption configuration of the formic acid on the surface of the catalyst, thereby playing a promoting role in the process of catalyzing the formic acid to prepare hydrogen.
(5) The catalyst of the invention can also be used in a plurality of fields such as heterogeneous catalytic reaction, hydrogen fuel cell, cathode corrosion prevention, boride target material, boride nozzle composite material, boride ceramic material, boride coating, boride surface coating film material, wear-resistant material, energy chemical industry, petrochemical industry, hydrocarbon bond activation, pharmacy, preparation of hydrogen-containing water and the like.
Drawings
FIG. 1 is a schematic view (a), tiB of a molten salt growth metal boride carrier 2 XRD spectrum (b) and Pt/TiB of nanocrystalline with calcination temperature 2 HAADF-STEM picture (c) (Pt content 12.0wt%, inset shows lattice spacing of Pt nanoparticles);
FIG. 2 is a Pt/TiB calcined at 600 ℃ 2 HAADF-STEM picture of (a picture is dispersed in TiB 2 Pt nanoparticles on surface, b-plot is Pt/TiB 2 HAADF plot of a region of the sample, c plot is Ti element profile corresponding to B plot, d plot is B element profile corresponding to B plot, e plot is Pt element profile corresponding to B plot);
FIG. 3 is a Pt/TiB calcined at different temperatures 2 HR-TEM pictures, TEM pictures and Pt particle size distribution plots; wherein figure a,d and g are calcined at 500 ℃; panels b, e and h are calcination at 600 ℃; figures c, f and i are calcined at 800 ℃;
FIG. 4 is a Pt/TiB calcined at 600 ℃ 2 TEM pictures (a) and HR-TEM pictures (b, c);
FIG. 5 is 800℃calcined Pt/TiB 2 HR-TEM pictures (a-c) and HAADF-STEM pictures (d-f);
FIG. 6 is a 600℃calcined Ag/TiB 2 TEM picture (a is 100nm, b is 5 nm);
FIG. 7 is a Pd/TiB calcined at 600 ℃ 2 TEM pictures of (a);
FIG. 8 is a Pd/TiB calcined at 600 ℃ 2 HR-TEM image of (2);
FIG. 9 is a 600℃calcined Au/TiB 2 TEM pictures of (a);
FIG. 10 is a 600℃calcined Au/TiB 2 HR-TEM image of (2);
FIG. 11 is a 600 ℃ calcined Ru/TiB 2 TEM pictures of (a);
FIG. 12 is a 600℃calcined Rh/TiB 2 TEM pictures of (a);
FIG. 13 is Pt/TiB 2 And XANES (a, c) and EXAFS spectra (b, d) of other comparative catalysts;
FIG. 14 is Pt/TiB 2 XPS spectra of other comparative catalysts (a is Ti 2p, B is B1 s, c is Pt 4 f);
FIG. 15 is Pt/TiB 2 And other comparative catalysts catalyze the comparison graph (b) of formic acid solution hydrogen production spectrogram (a) and conversion frequency (TOF);
FIG. 16 shows the demonstration of water molecules versus Pt/TiB using deuteration experiments, EPR and FT-IR 2 Catalytic formic acid solution hydrogen production;
FIG. 17 is formic acid concentration vs. Pt/TiB 2 An influence diagram of hydrogen production by catalyzing formic acid solution;
FIG. 18 is Pt/TiB 2 Stability effect graph of hydrogen production by catalyzing formic acid solution (graph a is a graph of different water volume contents in solvent versus Pt/TiB 2 Influence of hydrogen production performance by catalyzing formic acid solution decomposition and corresponding H 2 Generating a dual-logarithmic graph of initial rate and water concentration in solvent, and b is Pt/TiB 2 Catalytic formic acid decomposition hydrogen production diagram in different reaction systems, c is DMPO capturing marked Pt/TiB 2 And TiB 2 Respectively at HCOOH/H 2 O and HCOOH/C 2 H 5 Liquid EPR graph of reaction in OH solution, d graph is Pt/TiB 2 (i and ii) and TiB 2 (iii and iv) in HCOOH/H 2 The FT-IR spectrum obtained after 3 h reaction of O (i and iii) and anhydrous HCOOH (ii and iv) in solution was collected.
Detailed Description
The invention is further described below with reference to examples.
General examples
A high temperature sintering resistant catalyst comprising transition metal nanoparticles and a metal boride support supporting the transition metal nanoparticles; the transition metal nanoparticle comprises any one or more of group VIII and group IB transition metals; the chemical general formula of the metal boride carrier is M m B n Wherein M represents a metal, 0<m:n≤4。
Preferably, the mass ratio of the transition metal nano particles to the metal boride carrier is 0.01:100-20:100; further, the mass ratio of the transition metal nano particles to the metal boride carrier is 0.05:100-2:100; optimally, the mass ratio of transition metal nanoparticles to metal boride carriers is 1:100.
Preferably, the transition metal nano particles are metal simple substances or metal alloys; further, the metal simple substance is any one or more of Pt, cu, ag, au, co, rh, ir, fe, ru, ni and Pd; the metal alloy is Pt alloy; optimally, the metal simple substance is Pt; the metal alloy is PtCo alloy;
preferably, the transition metal nanoparticles have a size of less than 50 nanometers; further, the size of the transition metal nano particles is 1-10 nanometers; optimally, the transition metal nanoparticles have a size of 2.5 nanometers;
preferably, M is any one or more of Ti, zr, cr, hf and W; further, the metal boride carrier is TiB 2 、ZrB 2 、MgB 2 、Cr 2 B、HfB 2 And WB; optimally, the metal boride carrier is TiB 2 、
Preferably, the metal boride support is in the form of a shaped body of any size and geometry; further, the particle size of the metal boride carrier is 5-500 nanometers; the specific surface area of the metal boride carrier is 10-400 m 2 Per gram or 60-800 m 2 Per gram or 50-550 m 2 And/g. Optimally, the particle size of the metal boride carrier is 100 nanometers.
Preferably, the metal boride carrier is prepared by a molten salt synthesis method, a carbothermic reduction method, and a borothermic reduction method. Further, the metal boride carrier is prepared by a molten salt synthesis method, comprising: mixing and grinding nano metal oxide, boron powder, carbon powder, naCl and KCl, calcining at high temperature, washing with water, washing with alcohol, and drying.
Further, the preparation method of the metal boride carrier comprises the following steps:
taking nano metal oxide powder and boron powder as main reactants, and carbon powder as a reducing agent, wherein the molar ratio of the nano metal oxide to the boron powder to the carbon powder is 2:1:1-1:10:15; naCl and KCl are used as molten salt, and the mol ratio of NaCl to KCl is 1:0.5-2; the ratio of the total mass of the nano metal oxide to the total mass of the boron powder to the total mass of NaCl and KCl is 2:1-10; mixing and grinding the raw materials, placing the mixture into an alumina or platinum crucible, heating to 800-1600 ℃ under the protection of inert gas, keeping the temperature for 1-5 h at the temperature at the heating rate of 5-20 ℃/min, washing with water and ethanol after cooling to room temperature, removing impurities, and drying at 20-80 ℃ for 2-48 h to obtain the metal boride carrier.
Preferably, the nano metal oxide is TiO 2 、ZrO 2 、HfO 2 、WO 3 And Cr (V) 2 O 3 Any one or any plurality of the following; further preferred is TiO 2 。
Preferably, the carbon powder is any one or more of active carbon, graphite, carbon fiber and graphene; activated carbon is further preferred.
Preferably, the inert gas is nitrogen, argon or helium; argon is further preferred.
Preferably, the molar ratio of the nano metal oxide to the boron powder is 3:10, the weight ratio of the nano metal oxide to the carbon powder is 1:2, and the molar ratio of NaCl to KCl is 1:1;
preferably, the temperature is raised to 1000 ℃.
A method for synthesizing a high-temperature sintering-resistant catalyst comprises the following steps:
1) The transition metal nanoparticle and the metal boride carrier are prepared separately.
2) And (2) loading the transition metal nano particles prepared in the step (1) on the surface of a metal boride carrier or in the metal boride carrier to prepare a metal nano catalyst, then stabilizing the metal nano catalyst through heat treatment, and simultaneously removing ligands and pollutants on the surface of the transition metal nano particles to obtain the high-temperature sintering-resistant catalyst.
The other synthesis method of the high-temperature sintering-resistant catalyst comprises the following steps:
1) Preparing a metal boride carrier.
2) And (2) loading metal nano particles on the metal boride carrier material prepared in the step (1) by utilizing a transition metal precursor through an in-situ reduction method to prepare a metal nano catalyst, and then stabilizing the metal nano catalyst through heat treatment, and simultaneously removing ligands and pollutants on the surface of the transition metal nano particles to obtain the high-temperature sintering-resistant catalyst.
Preferably, the metal precursor is a nitrate, sulfate, chloride, oxalate, carbonate, citric acid, nitrate or a combination thereof of a transition metal. The selected reducing agents are sodium borohydride, borane and boroamine.
The high-temperature sintering-resistant catalyst has the performance of catalyzing the formic acid solution to prepare hydrogen. The formic acid solution is formic acid or formate water solution, and the concentration of the formic acid solution is 1-22 mol/L; further, the concentration of the formic acid solution was 10mol/L.
Further, the catalytic hydrogen production reaction can decompose formic acid or formate solution to produce hydrogen without the need for external energy, but does not preclude the use of external energy to increase the reaction rate. The term "applied energy" includes, but is not limited to, any one or more of mechanical energy, thermal energy, electrical energy, optical energy, and ultrasound.
Although the catalytic hydrogen production reaction can be carried out at 0 ℃, the hydrogen production reaction temperature can be 0-100 ℃ in order to achieve the optimal hydrogen production efficiency; preferably, the reaction temperature of the catalytic system is 0-30 ℃; preferably, the reaction temperature of the catalytic system is room temperature; more preferably, the reaction temperature of the catalytic system is 0-10 ℃; more preferably, the reaction temperature of the catalytic system is 0 ℃. The room temperature may be a standard room temperature (23±5 ℃), or may be a real room temperature.
The hydrogen production reaction further comprises an auxiliary agent selected from sodium formate, ethylenediamine, triethylamine, KOH and Na 2 CO 3 、K 2 CO 3 Any one or any plurality of NaOH.
In addition, the high-temperature sintering-resistant catalyst provided by the invention can be applied to the fields of heterogeneous catalytic reaction, hydrogen fuel cells, cathode corrosion prevention, boride targets, boride nozzle composite materials, boride ceramic materials, boride coatings, boride surface coating film materials, wear-resistant materials, energy chemical industry, petrochemical industry, hydrocarbon bond activation, pharmacy, preparation of hydrogen-containing water and the like. Furthermore, the hydrogen prepared by the high-temperature sintering-resistant catalyst can be used as a high-quality fuel in the energy chemical and petrochemical processes. Furthermore, the high-temperature sintering-resistant catalyst can be used for cathode corrosion prevention, boride targets, boride nozzle composite materials, boride ceramic materials, boride coatings, boride surface coating film materials and wear-resistant materials. Further, the high temperature sintering resistant catalyst can be used in pharmaceutical and medical fields, such as preparing medical hydrogen-containing water.
Example 1
The molar ratio was set to 3: tiO of 10 2 Mixing the powder 1, selecting mole The ratio is 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 1 and powder 2 and 0.5. 0.5 g nm carbon powder (purchased from aladine, particle size about 30 nm, the same applies below) were thoroughly mixed and ground for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale TiB 2 A crystal as shown in fig. 1 and 7.
Example 2
The molar ratio was set to 3: tiO of 10 2 Powder 1 was obtained by thoroughly mixing the powder/B, the molar ratio being chosen to be 2:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 2 and 0.6. 0.6 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1100 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale TiB 2 And (5) a crystal.
Example 3
The molar ratio was set to 2: tiO of 10 2 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 2:10 with powder 2 and 0.5. 0.5 g nm carbon powder and grinding for 20 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 900 o C, keeping the temperature at 2 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale TiB 2 And (5) a crystal.
Example 4
The molar ratio was set to 3: zrO of 10 2 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powderEnd 2 is molten salt, then the mass ratio will be 1:10 with powder 2 and 0.5. 0.5 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano ZrB 2 And (5) a crystal.
Example 5
The molar ratio was set to 4: zrO of 10 2 Powder 1 was obtained by thoroughly mixing the powder/B, the molar ratio being chosen to be 2:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 2:10 with powder 2 and 0.5. 0.5 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 900 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano ZrB 2 And (5) a crystal.
Example 6
The molar ratio was set to 3: cr of 10 2 O 3 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 2 and 0.5. 0.5 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale Cr 2 And B crystal.
Example 7
The molar ratio was set to 3:10 HfO 2 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 and powder 1 and powder 2 and 0.5. 0.5 g nanometer carbon powder are sufficientMix and grind for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale HfB 2 And (5) a crystal.
Example 8
The molar ratio was set to 3: WO 10 3 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 2 and 0.5. 0.5 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o And C, preserving the heat at the temperature of 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to finally obtain the nanoscale WB crystals.
Example 9
The molar ratio was set to 3: moO of 10 2 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 2 and 0.5. 0.5 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o And C, preserving the heat at the temperature of 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to finally obtain the nano-scale MoB crystal.
Example 10
The molar ratio was set to 3:10 to obtain powder 1 by thoroughly mixing MgO/B powder, wherein the molar ratio is 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 2 and 0.5. 0.5 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 900 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale MgB 2 And (5) a crystal.
Example 11
The molar ratio was set to 1:2: tiO of 10 2 /ZrO 2 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 2 and 0.8 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale TiB 2 And ZrB 2 And mixing the crystals.
Example 12
The molar ratio was set to 1:2: tiO of 10 2 /HfO 2 Powder B was thoroughly mixed to give powder 1, the molar ratio being chosen to be 1:1 NaCl/KCl mixed powder 2 is molten salt, and then the mass ratio is 1:10 with powder 2 and 0.8 g nm carbon powder and grinding for 10 min. Transfer of the final mixture into Al 2 O 3 In a crucible under argon atmosphere at 10 o The rate of C/min rises to 1000 o C, keeping the temperature at 1 h, cooling to room temperature, repeatedly boiling and centrifuging the calcined product in deionized water, washing with absolute ethyl alcohol for several times, and drying to obtain the nano-scale TiB 2 And HfB 2 And mixing the crystals.
Example 13
Platinum acetylacetonate is dissolved in oleylamine and heated to 110 f o C and incubating for 10 min to remove moisture, and then reducing the temperature to 102 o And C, adding the mixture of borane-tertiary butylamine complex dissolved in oleylamine into the reaction liquid, carrying out oil bath reaction on the mixture 3 and h, and centrifugally collecting the Pt nano particles. 500 mg of TiB is then added 2 Dispersing Pt nano particles (50 mg) prepared in advance into BAlcohol and stirred 3 h followed by centrifugal drying at 600 o C、H 2 Calcining 3 h under the protection of Ar mixed gas or nitrogen to obtain high-temperature sintering-resistant Pt/TiB 2 The catalyst is shown in fig. 1, 2, 3, 4, 7 and 8. It is apparent from the electron microscopy that Pt nanoparticles are coated with single or multi-layered TiB 2 The coating forms a core-shell structure, the average particle diameter of the Pt nano particles is only 2.37nm, and the phenomenon of high-temperature sintering growth does not occur. At the same time, pt and TiB are available from the characterization of synchrotron radiation 2 Characteristic Pt-B bonds are formed between the nano-particles, and the nano-particles have negative charges on the surfaces of the nano-particles according to XPS analysis.
Example 14
200 mg of TiB 2 Dispersing 10 mg Pt nano particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 800 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Pt/TiB 2 The catalyst is shown in fig. 3 and 5. From the electron microscopy it is evident that Pt nanoparticles are multilayered TiB 2 The coating forms a core-shell structure, the average particle diameter of the Pt nano particles is only 2.43nm, and the phenomenon of high-temperature sintering growth does not occur.
Example 15
100 mg of TiB 2 Dispersing 5 mg Pt nano particles prepared earlier into ethanol and stirring for 3 h, and then centrifugally drying at 500 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Pt/TiB 2 The catalyst is shown in figure 3. From the electron microscopy, it is evident that the Pt nanoparticles are coated with a monolayer of TiB 2 The coating forms a core-shell structure, the average particle diameter of the Pt nano particles is only 2.28nm, and the phenomenon of high-temperature sintering growth does not occur.
Example 16
600 mg of TiB 2 Dispersing 10 mg of Ag nano-particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Ag/TiB 2 The catalyst is shown in fig. 6. As apparent from the electron microscope imageAg nano particles are coated with TiB 2 The coating forms a core-shell structure, and the phenomenon of high-temperature sintering growth does not occur.
Example 17
300 mg of TiB 2 Dispersing 10 mg Pd nano-particles prepared in advance into ethanol and stirring for 3 h, then centrifugally drying, at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Pd/TiB 2 The catalyst is shown in fig. 6. From the electron microscope image, it is obvious that Pd nano-particles are coated with TiB 2 The coating forms a core-shell structure, and the phenomenon of high-temperature sintering growth does not occur.
Example 18
200 mg of TiB 2 Dispersing 5 mg Au nano-particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Au/TiB 2 The catalyst is shown in fig. 6. From the electron microscopy, it is evident that Au nanoparticles are coated with TiB 2 Cladding forms a core-shell structure.
Example 19
200 mg of ZrB 2 Dispersing 10 mg of Pt nano particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Pt/ZrB 2 A catalyst.
Example 20
500 mg of HfB 2 Dispersing 5 mg Pt nano particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Pt/HfB 2 A catalyst.
Example 21
500 mg of ZrB 2 Dispersing 10 mg of Ag nano-particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Ag/ZrB 2 A catalyst.
Example 22
200 mg of ZrB 2 Dispersing 5 mg Pd nano-particles prepared in advance into ethanol and stirring for 3 h, then centrifugally drying, at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Pd/ZrB 2 A catalyst.
Example 23
200 mg of ZrB 2 Dispersing 10 mg Au nano-particles prepared in advance into ethanol and stirring for 3 h, then centrifugally drying, and finally obtaining the nano-particles at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Au/ZrB 2 A catalyst.
Example 24
200 mg of TiB 2 Dispersing 10 mg of Cu nano-particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Cu/TiB 2 A catalyst.
Example 25
200 mg of TiB 2 Dispersing 10 mg Co nanometer particles prepared earlier into ethanol and stirring 3 h, centrifuging and drying, and mixing at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Co/TiB 2 A catalyst.
Example 26
200 mg of TiB 2 Dispersing with 6 mg of Rh nanometer particles prepared earlier in ethanol and stirring for 3 h, and centrifuging and drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Rh/TiB 2 A catalyst.
Example 27
200 mg of TiB 2 Dispersing 5 mg Ir nano particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Ir/TiB 2 A catalyst.
Example 28
200 mg of TiB 2 Is prepared in earlier stage5 mg Ni nanoparticles of (C) were dispersed in ethanol and stirred for 3 h, followed by centrifugal drying, at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Ni/TiB 2 A catalyst.
Example 29
200 mg of TiB 2 Dispersing 10 mg Fe nano particles prepared in advance into ethanol and stirring for 3 h, then centrifugally drying, and finally obtaining the nano-particles at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Fe/TiB 2 A catalyst.
Example 30
200 mg of TiB 2 Dispersing 2 mg Ru nano-particles prepared in advance into ethanol and stirring for 3 h, and then centrifugally drying at 600 o C、H 2 Calcining 4 h under the protection of Ar mixed gas to obtain high-temperature sintering-resistant Ru/TiB 2 A catalyst.
Example 31
The catalytic formic acid decomposition reaction was carried out in a quartz tube of 55 mL, the oxygen in the tube was removed by introducing nitrogen into a 5 mL formic acid solution containing 20mg catalyst, then sealing with a silica gel plug and polytetrafluoroethylene film, placing it on a stirrer for water bath reaction of 3H, extracting 400 uL gas from the tube with a microsyringe every 0.5H and injecting into GC-TCD for detection of H 2 、O 2 、CO 2 And CO, etc.
Example 32
20mg,600 are taken o Pt/TiB calcined at C temperature 2 The catalyst and other comparative catalysts were placed in an aqueous solution containing 10mol/L formic acid, nitrogen was introduced to remove oxygen from the tube, and then the tube was sealed with a silica gel plug and polytetrafluoroethylene film, which was placed in a stirrer water bath 25 o The reaction was carried out for several hours under C. As shown in fig. 9, 600 o Pt/TiB calcined at C temperature 2 The catalyst has optimal hydrogen production performance and apparent activation energy which is higher than that of pure TiB 2 Near 29kJ/mol lower.
Example 33
20mg,600 are taken o Pt/TiB calcined at C temperature 2 Catalytic reactionThe catalyst and other comparative catalyst were placed in an aqueous solution containing 10mol/L formic acid, nitrogen was introduced to remove oxygen from the tube, and then the tube was sealed with a silica gel plug and a polytetrafluoroethylene film, which was placed in a stirrer water bath 25 o The reaction is carried out for several hours under the condition C, and the catalytic hydrogen production performance is shown in the table 1. The calcination temperature in Table 1 refers to the catalyst at H 2 The calcination temperature in Ar mixed gas is 5 hours; the mass specific activity means H generated on a catalyst per unit mass 2 The content is as follows; TOF is the frequency of conversion of acid molecules at the surface of the catalyst per unit time. As can be seen from Table 1, pt/TiB 2 The mass specific activity and TOF were both 1-2 orders of magnitude higher than the other supported catalysts (entries 1-17). At the same time, the calcination temperature has a certain influence on the catalytic activity of the catalyst, 600 o C calcined Pt/TiB 2 With optimal catalytic activity (entry 6 and entries 18-21).
Table 1 comparison of hydrogen production performance from formic acid catalyzed by different catalysts; the catalyst amount was 20mg, the reaction temperature was 25℃and the formic acid concentration was 10mol/L.
Example 34
20mg,600 are taken o Pt/TiB calcined at C temperature 2 Placing the catalyst into aqueous solution of formic acid with different concentration, introducing nitrogen gas to remove oxygen in the test tube, sealing with silica gel plug and polytetrafluoroethylene film, and placing in water bath 25 on a stirrer o The reaction is carried out for a plurality of hours under the condition of C, the catalytic hydrogen production performance is shown in figure 10, and 10mol/L formic acid has the optimal catalytic performance.
Example 35
20mg,600 are taken o Pt/TiB calcined at C temperature 2 Placing the catalyst into 10mol/L formic acid water solution, introducing nitrogen gas to remove oxygen in the test tube, sealing with silica gel plug and polytetrafluoroethylene film, and placing in water bath 25 on a stirrer o Taking out the catalyst after reacting for several hours under the condition of C, drying, then carrying out the experiment of hydrogen production by formic acid again, repeating the steps for 7 times,the results are shown in FIG. 11, and it can be seen that Pt/TiB 2 The catalyst has high stability.
Example 36
20mg Pt/TiB was taken 2 Placing the catalyst into formic acid solution with different concentrations, introducing nitrogen to remove oxygen in the test tube, sealing with silica gel plug and polytetrafluoroethylene film, and placing in water bath 25 on a stirrer o The reaction was carried out under C for several hours, and as shown in fig. 12, the hydrogen generation amount increased with the increase of the water amount, and the relationship thereof was in accordance with the first order kinetics.
Example 37
20 mg Pt/TiB was taken 2 In the catalyst, deuteration experiments of hydrogen production by formic acid solution are carried out, and as shown in fig. 12, hydrogen in the hydrogen gas is from hydrogen in formic acid.
Example 38
20 mg Pt/TiB was taken 2 The catalyst was placed in an aqueous formic acid solution, nitrogen was introduced to remove oxygen in the test tube, and then an EPR experiment was performed for DMPO capture, as shown in fig. 12, in which hydrogen radicals were generated in the reaction.
Example 39
Go to 20 mg Pt/TiB 2 The catalyst is put into formic acid aqueous solution, nitrogen is introduced to remove oxygen in a test tube, after a period of reaction, the catalyst is taken out to perform FT-IR experiment, as shown in FIG. 12, when formic acid is in Pt/TiB 2 After the catalyst is adsorbed, the adsorption mode of formic acid is changed from trans to cis, which is more favorable for the dehydrogenation of formic acid.
The raw materials and equipment used in the invention are common raw materials and equipment in the field unless specified otherwise; the methods used in the present invention are conventional in the art unless otherwise specified.
The foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and any simple modification, variation and equivalent transformation of the above embodiment according to the technical substance of the present invention still fall within the scope of the technical solution of the present invention.
Claims (4)
1. The application of the high-temperature sintering-resistant catalyst in catalyzing formic acid solution to prepare hydrogen is characterized in that: the high-temperature sintering-resistant catalyst comprises transition metal nano particles and a metal boride carrier for loading the transition metal nano particles; the mass ratio of the transition metal nano particles to the metal boride carrier is 0.05:100-2:100;
the transition metal nano particles are metal simple substances, and the metal simple substances are Pt; the size of the transition metal nano particles is 1-10 nanometers;
the metal boride carrier is TiB 2 The method comprises the steps of carrying out a first treatment on the surface of the The grain diameter of the metal boride carrier is 5-500 nanometers; the specific surface area of the metal boride carrier is 10-400 m 2 Per gram or 60-800 m 2 Per gram or 50-550 m 2 /g；
The synthesis method of the high-temperature sintering-resistant catalyst comprises the following steps:
1) Preparing transition metal nano particles and a metal boride carrier respectively;
2) Loading the transition metal nano particles prepared in the step 1) on the surface of a metal boride carrier or in the metal boride carrier to prepare a metal nano catalyst, then stabilizing the metal nano catalyst through heat treatment, and simultaneously removing ligands and pollutants on the surface of the transition metal nano particles to obtain a high-temperature sintering-resistant catalyst;
the preparation method of the metal boride carrier comprises the following steps: taking nano metal oxide powder and boron powder as main reactants, and carbon powder as a reducing agent, wherein the molar ratio of the nano metal oxide to the boron powder to the carbon powder is 2:1:1-1:10:15; naCl and KCl are used as molten salt, and the mol ratio of NaCl to KCl is 1:0.5-2; the ratio of the total mass of the nano metal oxide to the total mass of the boron powder to the total mass of NaCl and KCl is 2:1-10; mixing and grinding the raw materials, placing the raw materials into an alumina or platinum crucible, heating to 800-1600 ℃ under the protection of inert gas, keeping the temperature for 1-5 h at a heating rate of 5-20 ℃/min, cooling to room temperature, washing with water and ethanol, removing impurities, and drying at 20-80 ℃ for 2-48 h to obtain a metal boride carrier;
The formic acid solution is formic acid or formate water solution;
the concentration of the formic acid solution is 1-22 mol/L;
the reaction temperature of hydrogen production is 0-10 ℃.
2. The use according to claim 1, wherein: the concentration of the formic acid solution is 10mol/L.
3. Use according to claim 1 or 2, characterized in that: the hydrogen production reaction also comprises an auxiliary agent; the auxiliary agent is selected from sodium formate, ethylenediamine, triethylamine, KOH and Na 2 CO 3 、K 2 CO 3 Any one or any plurality of NaOH.
4. The use according to claim 1, wherein:
the mass ratio of the transition metal nano particles to the metal boride carrier is 1:100;
the size of the transition metal nanoparticle is 2.5 nanometers;
the particle size of the metal boride carrier was 100 nm.
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