CN109926070B - Mn (manganese)0.5Cd0.5S/WO3Preparation method of Au supported photocatalyst - Google Patents

Abstract

The invention discloses Mn_0.5Cd_0.5S/WO₃Au supported photocatalyst and preparation method thereof, belonging toThe field of inorganic functional materials. Mixing WO₃And Au Supported to Mn_0.5Cd_0.5Preparation of supported Mn on S_0.5Cd_0.5An S photocatalyst, wherein: mn_0.5Cd_0.5S、WO₃The mass ratio of the Au to the Au is 1:0.2-0.5: 0.02-0.05. In the present invention, Mn_0.5Cd_0.5S and WO₃A Z-system photocatalytic system is formed, and the electron-hole recombination efficiency is reduced; introduction of nano Au particles not only can be combined with Mn_0.5Cd_0.5S/WO₃The system forms surface plasma resonance to enhance light absorption and is beneficial to Mn_0.5Cd_0.5The photocatalytic activity of the supported catalyst is greatly improved by the migration of S conduction band electrons.

Description

Mn (manganese)0.5Cd0.5S/WO3Preparation method of Au supported photocatalyst

Technical Field

The invention belongs to the technical field of inorganic materials, and particularly relates to Mn_0.5Cd_0.5S/WO₃Au supported photocatalyst and a preparation method thereof.

Background

With the continuous development of society, the energy crisis is increasingly serious, and the environmental pollution caused by the continuous exploitation and consumption of fossil fuels is continuously aggravated, so that a novel, reliable and environment-friendly energy source is urgently needed to be developed to solve the current problems. Hydrogen is the most abundant element in nature, the highest content substance in universe, accounting for about 75%, and hydrogen energy is an efficient, clean and sustainable 'carbon-free' energy source. The generation of the photocatalysis technology can utilize solar energy to decompose water to prepare hydrogen, thereby not only solving the energy crisis, but also protecting the environment.

Mn_0.5Cd_0.5The S solid solution has good visible light absorption capacity and a narrower and adjustable forbidden band width, thereby being widely concerned by people and being a potential photocatalytic hydrogen production material. But due to Mn_0.5Cd_0.5The S solid solution is rapidly combined with electrons and holes under the action of light, the quantum efficiency is low, and the photocatalytic activity of the S solid solution is limited. The invention relates to WO₃And Au negativeLoaded on Mn_0.5Cd_0.5S surface, Mn_0.5Cd_0.5S and WO₃A direct Z-system photocatalytic system is formed, the electron-hole recombination efficiency is reduced, more photogenerated electrons are used in the process of photolyzing water to produce hydrogen, and Mn is greatly improved_0.5Cd_0.5The quantum efficiency of S and the hydrogen production efficiency by photolysis of water; the addition of Au nanoparticles can not only enhance light absorption, but also promote electron transfer rate and reduce the recombination of photo-generated electrons and holes, thereby further improving the photocatalytic activity.

Disclosure of Invention

The invention provides Mn which is simple to operate and easy to realize_0.5Cd_0.5S/WO₃Preparation method of Au supported photocatalyst and Mn prepared by method_0.5Cd_0.5S/WO₃The Au supported photocatalyst has the advantages of high quantum efficiency, good photocatalytic hydrogen production activity and the like.

Mn (manganese)_0.5Cd_0.5S/WO₃/Au Supported photocatalyst, prepared by reacting WO₃And Au Supported to Mn_0.5Cd_0.5S, the structure is characterized in that: mn_0.5Cd_0.5S、WO₃The mass ratio of the Au to the Au is 1:0.2-0.5: 0.02-0.05. Mn in the catalyst_0.5Cd_0.5S、WO₃The mass ratio of the Au to the Au is 1:0.2-0.5: 0.02-0.05; diffraction peaks exist at 13.9 °, 22.8 °, 25.0 °, 26.8 °, 28.1 °, 28.6 °, and 36.5 ° in XRD; binding energies in XPS are present at 35.9eV, 38.2eV, 84.3eV, 88.0eV, 161.3eV, 162.4eV, 404.85eV, 411.6eV, 530.35eV, 641.1eV, and 652.3 eV. The above data allows for an upper and lower 0.1 deviation.

Pure WO can be obviously observed in an XRD data analysis chart₃Four diffraction peaks exist at 13.9 degrees, 22.8 degrees, 28.1 degrees and 36.5 degrees, which respectively correspond to a crystal face (100), a crystal face (001), a crystal face (200) and a crystal face (201), and WO₃The XRD spectrum of the sample was consistent with that of standard card JCPDS No.75-2187, which shows WO₃The samples were successfully synthesized. Pure Mn_0.5Cd_0.5As is evident from the figure, the S solid solution has three diffraction peaks at 25.0 degrees, 26.8 degrees and 28.6 degrees, which respectively correspond to a (100) crystal face and a (002) crystal faceAnd (101) plane, consistent with previously reported literature. Composite sample Mn_0.5Cd_0.5S/WO₃In XRD pattern of (B), except for Mn_0.5Cd_0.5Besides the diffraction peak of S, WO can be obviously observed₃Crystal planes of (100), (001), (200) and (201) of (A) to (B) of (B) to (B) of (A) illustrate WO₃With Mn_0.5Cd_0.5And S is successfully compounded. Mn_0.5Cd_0.5S/WO₃Presence of Mn in Au samples_0.5Cd_0.5S and WO₃But no Au diffraction peak is observed in the diffraction pattern, which may be caused by the low content of Au or the weak Au nanoparticle diffraction peak.

XPS analysis of Mn_0.5Cd_0.5S/WO₃The element composition of the Au sample can be seen from the graph, and Cd 3d can be seen from the graph_5/2And Cd 3d_3/2Has a binding energy of 404.85eV and 411.6eV, Mn 2p_3/2And Mn 2p_1/2The binding energies of (A) are 641.1eV and 652.3 eV. Indicating that the sample contains Cd element and Mn element. S2 p in the map_3/2And S2 p_1/2Has a binding energy of 161.3eV and 162.4eV, respectively, and a W4 f energy of_5/2And W4 f_7/2The binding energies of (A) were 35.9eV and 38.2 eV. The sample was indicated to contain S element and W element. The binding energy in the map was 530.35eV, corresponding to WO₃Peak of O element in the middle W-O bond. In the atlas Au 4f_7/2And Au 4f_5/2The binding energy of (A) is 84.3eV and 88.0eV, the existence of Au element in the sample is indicated, and the reason that the Au diffraction peak is not detected due to the low content of Au or the weak diffraction peak of the nano Au particle in the XRD spectrum is also proved. XPS spectra observes that the three-system composite material contains Cd, Mn, S, W, O and Au elements, and further proves that Mn is successfully prepared_0.5Cd_0.5S/WO₃a/Au composite material.

Mn_0.5Cd_0.5S/WO₃the/Au composite photocatalyst is characterized by XRD and XPS, and XRD shows that Mn exists_0.5Cd_0.5S and WO₃The diffraction peak of the compound is not found, and other impurity peaks are not found, which indicates that the prepared sample has high purity; meanwhile, the Au diffraction peak is not detected because the loading amount of Au is small. XPS shows Mn produced_0.5Cd_0.5S/WO₃The Au sample contains Cd, Mn, S, Au, W and O elements, and further proves that Mn exists in the prepared sample_0.5Cd_0.5S、WO₃And Au is present.

The preparation method of the composite photocatalyst provided by the invention comprises the following steps:

mn (manganese)_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps:

1) dissolving sodium tungstate dihydrate and sodium chloride in deionized water, adjusting the pH value of the solution to 1.5-2.5 by using hydrochloric acid, then carrying out hydrothermal reaction on the solution at 160-180 ℃, and obtaining WO after treatment₃And (3) solid powder.

Further, in the technical scheme, the mass ratio of the sodium tungstate to the sodium chloride is 5: 1.

2) Dissolving L-cystine in deionized water, and adjusting the pH value of the solution to 10-11 by using NaOH to form a mixed solution A; dissolving cadmium acetate dihydrate and manganese acetate dihydrate in deionized water to form a mixed solution B; dropwise adding the mixed solution B into the mixed solution A, carrying out hydrothermal reaction on the solution at the temperature of 120-140 ℃, and obtaining Mn after treatment_0.5Cd_0.5And (3) S nanoparticles.

Further, in the technical scheme, the molar ratio of the cadmium acetate to the manganese acetate is 1: 1.

3) Mn obtained in the step 2)_0.5Cd_0.5S nanoparticles and WO obtained in step 1)₃Dispersing the powder in methanol solution, performing ultrasonic treatment, and performing circulating reflux at 60-90 deg.C; mn is obtained after the treatment_0.5Cd_0.5S/WO₃And (c) a complex.

Further, in the above technical means, Mn_0.5Cd_0.5S/WO₃The mass ratio is 1: 0.2-0.5.

4) Mn obtained in the step 3)_0.5Cd_0.5S/WO₃Dispersing the compound in deionized water, then dropwise adding chloroauric acid solution for ultrasonic treatment, and then adding NaBH₄Solution, post-treatment to obtain Mn_0.5Cd_0.5S/WO₃Au supported photocatalyst.

Further, in the above technical means, Mn_0.5Cd_0.5S、WO₃The mass ratio of the Au to the Au is 1:0.2-0.5: 0.02-0.05.

Mn prepared according to the above method_0.5Cd_0.5S/WO₃The Au supported photocatalyst is used for hydrogen production experiment:

the operating conditions are as follows: light source: a 300W xenon lamp; amount of catalyst: 0.05 g; concentration of the sacrificial agent: 0.1mol/L of Na₂S and 0.1mol/L of Na₂SO₃. As can be seen from the figure, pure Mn_0.5Cd_0.5The hydrogen production rate of the S catalyst is 23.17 mu mol h^-1And Mn_0.5Cd_0.5S/WO₃The hydrogen production rate of Au-supported photocatalyst reaches up to 90.28 mu mol h^-1And obviously enhanced photocatalytic hydrogen production performance is shown.

To further describe the above Mn_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst comprises the following typical operation steps:

(1)WO₃the preparation of (1): weighing a certain mass of sodium tungstate dihydrate and sodium chloride, dissolving the sodium tungstate dihydrate and the sodium chloride in deionized water at a mass ratio of 5:1, continuously stirring for 6 hours, then adjusting the pH value of the solution to 2 by using concentrated hydrochloric acid, continuously stirring for 3 hours, transferring the solution to a polytetrafluoroethylene kettle after stirring is finished, and keeping the solution for 24 hours at the temperature of 160-180 ℃. Cooling to room temperature after the reaction is finished, carrying out suction filtration and washing on the obtained product by deionized water and absolute ethyl alcohol, and carrying out vacuum drying to obtain WO₃And (3) solid powder.

(2)Mn_0.5Cd_0.5Preparing S nano particles: weighing a certain mass of L-cystine, dissolving in deionized water, and then adjusting the solution with 6M NaOH to make the pH of the solution equal to 10.6 to form a mixed solution A; weighing a certain mass of cadmium acetate dihydrate and manganese acetate dihydrate, and dissolving the cadmium acetate dihydrate and the manganese acetate dihydrate in deionized water, wherein the molar ratio of the cadmium acetate to the manganese acetate is 1:1, so as to form a mixed solution B; dropwise adding the mixed solution B into the mixed solution A under stirring, transferring the obtained uniformly-mixed solution into a polytetrafluoroethylene kettle, keeping the solution at the temperature of 120-140 ℃ for 10 hours, cooling to room temperature after the reaction is finished, and passing the obtained product through deionized waterAnd absolute ethyl alcohol is filtered, washed and dried in vacuum to obtain Mn_0.5Cd_0.5And (3) S nanoparticles.

(3)Mn_0.5Cd_0.5S/WO₃Preparation of composite sample: mn obtained in the step (2)_0.5Cd_0.5S nanoparticles and WO obtained in step 1)₃Powder according to Mn_0.5Cd_0.5S/WO₃Mixing and dispersing the materials in a methanol solution at a mass ratio of 1:0.2-0.5, performing ultrasonic treatment for 30min, and performing circulating reflux in a water bath kettle at 60-90 ℃ for 3 h; cooling to room temperature after the reaction is finished, carrying out suction filtration washing on the obtained product by deionized water and absolute ethyl alcohol, and drying in vacuum to obtain Mn_0.5Cd_0.5S/WO₃And (c) a complex.

(4)Mn_0.5Cd_0.5S/WO₃Preparation of Au complex sample: mn obtained in the step (3)_0.5Cd_0.5S/WO₃Dispersing the compound in deionized water, dropwise adding chloroauric acid solution, performing ultrasound for 30min, adding sodium borohydride aqueous solution after the ultrasound is finished, continuing stirring for 3h, after the reaction is completed, performing suction filtration washing, vacuum drying and grinding on the obtained product through deionized water and absolute ethyl alcohol to obtain Mn_0.5Cd_0.5S、WO₃Mn in a mass ratio of 1:0.2-0.5:0.02-0.05 to Au_0.5Cd_0.5S/WO₃Au supported photocatalyst.

The invention has the beneficial effects that:

the Z-system photocatalyst is prepared, and the introduction of the nano Au particles can be combined with Mn_0.5Cd_0.5S and WO₃Form surface plasma resonance to accelerate Mn_0.5Cd_0.5The migration rate of electrons on the conduction band of S reduces the recombination of photo-generated electrons and holes, and further improves the Mn of a Z-system_0.5Cd_0.5S/WO₃The hydrogen production performance of Au photocatalysis.

Drawings

FIG. 1 shows Mn prepared in example 1 of the present invention_0.5Cd_0.5S、Mn_0.5Cd_0.5S/WO₃、 Mn_0.5Cd_0.5S/WO₃XRD pattern of Au;

in FIG. 2, a-g are Mn prepared in example 1 of the present invention_0.5Cd_0.5S/WO₃XPS spectra of Au supported photocatalyst;

FIG. 3 shows Mn prepared in example 1 of the present invention_0.5Cd_0.5S、Mn_0.5Cd_0.5S/WO₃、 Mn_0.5Cd_0.5S/WO₃Hydrogen efficiency diagram of Au photolysis water.

The specific implementation mode is as follows:

the present invention is further described below with reference to examples. It should be noted that the present invention is not limited to the following embodiments.

Example 1

1)WO₃The preparation of (1): weighing 2gNa₂WO₄-2H₂O and 0.4g NaCl were dissolved in 30mL deionized water and stirring was continued for 6h, then the pH of the solution was adjusted to 2 with concentrated hydrochloric acid and stirring was continued for 3h, after completion of stirring the solution was transferred to a 50mL teflon kettle and maintained at 160 ℃ for 24 h. Cooling to room temperature after the reaction is finished, filtering and washing the obtained product by deionized water and absolute ethyl alcohol, and drying in vacuum to obtain WO₃And (3) solid powder.

2)Mn_0.5Cd_0.5Preparing S nano particles: weighing 2.884g of L-cystine, dissolving in 40mL of deionized water, and then adjusting the solution with 6M NaOH to make the pH of the solution be 10.6 to form a mixed solution A; weighing 0.532g Cd (CH)₃COO)₂-2H₂O and 0.490g Mn (CH)₃COO)₂-2H₂Dissolving O in 25mL of deionized water to form a B mixed solution; dropwise adding the mixed solution B into the mixed solution A under stirring to obtain a uniformly mixed solution, transferring the uniformly mixed solution into a 100mL polytetrafluoroethylene kettle, keeping the solution at 120 ℃ for 10 hours, cooling to room temperature after the reaction is finished, performing suction filtration and washing on the obtained product through deionized water and absolute ethyl alcohol, and performing vacuum drying to obtain Mn_0.5Cd_0.5And (3) S nanoparticles.

3)Mn_0.5Cd_0.5S/WO₃Preparation of composite sample: weighing 0.2gMn obtained in step (2)_0.5Cd_0.5S nanoparticles and 0.04gWO obtained in step 1)₃Powder mixing componentDispersing in 50mL methanol solution, performing ultrasonic treatment for 30min, and performing circulating reflux in a water bath kettle at 60 deg.C for 4 h; cooling to room temperature after the reaction is finished, carrying out suction filtration washing on the obtained product by deionized water and absolute ethyl alcohol, and drying in vacuum to obtain Mn_0.5Cd_0.5S/WO₃And (c) a complex.

4)Mn_0.5Cd_0.5S/WO₃Preparation of Au complex sample: weighing 0.2gMn obtained in step (3)_0.5Cd_0.5S/WO₃The complex was dispersed in 30mL of deionized water, followed by dropwise addition of a chloroauric acid solution (m)_Mn0.5Cd0.5S:m_Au1:0.04), performing ultrasonic treatment for 30min, and adding 40mL of sodium borohydride aqueous solution (n) after the ultrasonic treatment is finished_NaHB4:n_AuStirring for 3 hours, after the reaction is completed, carrying out suction filtration washing, vacuum drying and grinding on the obtained product by using deionized water and absolute ethyl alcohol to obtain Mn_0.5Cd_0.5S/WO₃Au supported photocatalyst.

The Mn produced is evident from FIG. 1_0.5Cd_0.5S/WO₃Presence of Mn in Au samples_0.5Cd_0.5S and WO₃Diffraction peak of (2) indicating Mn produced_0.5Cd_0.5S and WO₃The purity of the sample is high. However, no Au diffraction peak was observed in the diffraction pattern, which may be caused by the low content of Au or the weak Au nanoparticle diffraction peak. Successful loading of nano-Au particles can be further confirmed by XPS.

The Mn produced is evident from FIG. 2_0.5Cd_0.5S/WO₃The Au sample contains Cd, Mn, S, Au, W and O elements, and further proves that Mn exists in the prepared sample_0.5Cd_0.5S、WO₃And Au is present.

From FIG. 3, it can be seen that the prepared three-system Mn_0.5Cd_0.5S/WO₃Au sample hydrogen production ratio two-system Mn_0.5Cd_0.5S/WO₃And pure Mn_0.5Cd_0.5The S sample has high hydrogen production (wherein, pure Mn)_0.5Cd_0.5The hydrogen production rate of the S catalyst is 23.17 mu mol h^-1，Mn_0.5Cd_0.5S/WO₃The hydrogen production efficiency is 48.66 mu mol h^-1,Mn_0.5Cd_0.5S/WO₃The hydrogen production rate of Au-supported photocatalyst reaches up to 90.28 mu mol h^-1). Illustrating the nano Au particles and WO₃The introduction of the photocatalyst effectively enhances the photocatalytic performance.

Example 2

1)WO₃The preparation of (1): weighing 1.5g Na₂WO₄-2H₂O and 0.3g NaCl were dissolved in 30mL deionized water and stirring was continued for 6h, then the pH of the solution was adjusted to 2 with concentrated hydrochloric acid and stirring was continued for 3h, after completion of stirring the solution was transferred to a 50mL teflon kettle and maintained at 160 ℃ for 24 h. Cooling to room temperature after the reaction is finished, filtering and washing the obtained product by deionized water and absolute ethyl alcohol, and drying in vacuum to obtain WO₃And (3) solid powder.

2)Mn_0.5Cd_0.5Preparing S nano particles: weighing 2.163g of L-cystine, dissolving in 40mL of deionized water, and then adjusting the solution with 6M NaOH to make the pH of the solution be 10.6 to form a mixed solution A; weighing 0.399g Cd (CH)₃COO)₂-2H₂O and 0.368g Mn (CH)₃COO)₂-2H₂Dissolving O in 25mL of deionized water to form a B mixed solution; dropwise adding the mixed solution B into the mixed solution A under stirring to obtain a uniformly mixed solution, transferring the uniformly mixed solution into a 100mL polytetrafluoroethylene kettle, keeping the solution at 140 ℃ for 10 hours, cooling to room temperature after the reaction is finished, performing suction filtration and washing on the obtained product through deionized water and absolute ethyl alcohol, and performing vacuum drying to obtain Mn_0.5Cd_0.5And (3) S nanoparticles.

3)Mn_0.5Cd_0.5S/WO₃Preparation of composite sample: weighing 0.15gMn obtained in step (2)_0.5Cd_0.5S nanoparticles and 0.045gWO from step 1)₃Mixing and dispersing the powder in 50mL of methanol solution, performing ultrasonic treatment for 30min, and performing circulating reflux in a water bath kettle at 80 ℃ for 3 h; after the reaction is cooled to room temperature, the obtained product is filtered, washed and dried in vacuum by deionized water and absolute ethyl alcohol to obtain Mn_0.5Cd_0.5S/WO₃And (c) a complex.

4)Mn_0.5Cd_0.5S/WO₃Preparation of Au complex sample: weighing 0.15gMn obtained in step (3)_0.5Cd_0.5S/WO₃The complex was dispersed in 30mL of deionized water, followed by dropwise addition of a chloroauric acid solution (m)_Mn0.5Cd0.5S:m_Au1:0.04), performing ultrasonic treatment for 30min, and adding 30mL of sodium borohydride aqueous solution (n) after the ultrasonic treatment is finished_{NaHB 4}:n_AuStirring for 3 hours, after the reaction is completed, carrying out suction filtration washing, vacuum drying and grinding on the obtained product by using deionized water and absolute ethyl alcohol to obtain Mn_0.5Cd_0.5S/WO₃Au supported photocatalyst.

Example 3

1)WO₃The preparation of (1): weighing 3gNa₂WO₄-2H₂O and 0.6g NaCl were dissolved in 30mL deionized water and stirring was continued for 6h, then the pH of the solution was adjusted to 2 with concentrated hydrochloric acid and stirring was continued for 3h, after completion of stirring the solution was transferred to a 50mL teflon kettle and maintained at 160 ℃ for 24 h. Cooling to room temperature after the reaction is finished, filtering and washing the obtained product by deionized water and absolute ethyl alcohol, and drying in vacuum to obtain WO₃And (3) solid powder.

2)Mn_0.5Cd_0.5Preparing S nano particles: weighing 3.605g of L-cystine, dissolving in 40mL of deionized water, and adjusting the solution with 6M NaOH to make the pH of the solution be 10.6 to form a mixed solution A; 0.665g of Cd (CH) was weighed₃COO)₂-2H₂O and 0.613g Mn (CH)₃COO)₂-2H₂Dissolving O in 25mL of deionized water to form a B mixed solution; dropwise adding the mixed solution B into the mixed solution A under stirring to obtain a uniformly mixed solution, transferring the uniformly mixed solution into a 100mL polytetrafluoroethylene kettle, keeping the solution at 140 ℃ for 10 hours, cooling to room temperature after the reaction is finished, performing suction filtration and washing on the obtained product through deionized water and absolute ethyl alcohol, and performing vacuum drying to obtain Mn_0.5Cd_0.5And (3) S nanoparticles.

3)Mn_0.5Cd_0.5S/WO₃Preparation of composite sample: weighing 0.25gMn obtained in step (2)_0.5Cd_0.5S nanoparticles and 0.075gWO from step 1)₃The powder is mixed and dispersed in 50mL of the powder APerforming ultrasonic treatment in alcohol solution for 30min, and performing circulating reflux in 90 deg.C water bath for 3 hr; cooling to room temperature after the reaction is finished, carrying out suction filtration washing on the obtained product by deionized water and absolute ethyl alcohol, and drying in vacuum to obtain Mn_0.5Cd_0.5S/WO₃And (c) a complex.

4)Mn_0.5Cd_0.5S/WO₃Preparation of Au complex sample: weighing 0.25gMn obtained in step (3)_0.5Cd_0.5S/WO₃The complex was dispersed in 30mL of deionized water, followed by dropwise addition of a chloroauric acid solution (m)_Mn0.5Cd0.5S:m_Au1:0.04), performing ultrasonic treatment for 30min, and adding 50mL of sodium borohydride aqueous solution (n) after the ultrasonic treatment is finished_NaHB4:n_AuStirring for 3 hours, after the reaction is completed, carrying out suction filtration washing, vacuum drying and grinding on the obtained product by using deionized water and absolute ethyl alcohol to obtain Mn_0.5Cd_0.5S/WO₃Au supported photocatalyst.

Example 4

Hydrogen production experiment:

the operating conditions are as follows: light source: a 300W xenon lamp; amount of catalyst: 0.05 g; concentration of the sacrificial agent: 0.1mol/L Na₂S and 0.1mol/L Na₂SO₃. As can be seen from FIG. 3, pure Mn_0.5Cd_0.5The hydrogen production rate of the S catalyst is 23.17 mu mol g^-1h^-1While Mn obtained in example 1 was used_0.5Cd_0.5S/WO₃The hydrogen production rate of Au-supported photocatalyst reaches up to 90.28 mu mol g^-1h^-1And obviously enhanced photocatalytic hydrogen production performance is shown. The results shown in the attached figures 1, 2 and 3 prove that Mn with enhanced photocatalytic hydrogen production performance can be successfully prepared_0.5Cd_0.5S/WO₃Au supported photocatalyst.

The composite photocatalyst prepared in the embodiment 2-3 is adopted to obtain similar hydrogen production effect.

The foregoing embodiments have described the general principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the present invention, and that various changes and modifications may be made without departing from the scope of the principles of the present invention, and the invention is intended to be covered by the appended claims.

Claims (10)

1. Mn (manganese)_0.5Cd_0.5S/WO₃The Au-supported photocatalyst is characterized in that: mn in the catalyst_0.5Cd_0.5S、WO₃The mass ratio of the Au to the Au is 1:0.2-0.5: 0.02-0.05; diffraction peaks exist at 13.9 °, 22.8 °, 25.0 °, 26.8 °, 28.1 °, 28.6 °, and 36.5 ° in XRD; binding energies in XPS are present at 35.9eV, 38.2eV, 84.3eV, 88.0eV, 161.3eV, 162.4eV, 404.85eV, 411.6eV, 530.35eV, 641.1eV, and 652.3 eV.

2. An Mn as set forth in claim 1_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps:

1) dissolving sodium tungstate dihydrate and sodium chloride in deionized water, adjusting the pH value of the solution to 1.5-2.5 by using hydrochloric acid, then carrying out hydrothermal reaction on the solution at 160-180 ℃, and obtaining WO after treatment₃Powder;

2) dissolving L-cystine in deionized water, and adjusting the pH value of the solution to 10-11 by using NaOH to form a mixed solution A; dissolving cadmium acetate dihydrate and manganese acetate dihydrate in deionized water to form a mixed solution B; dropwise adding the mixed solution B into the mixed solution A, then carrying out hydrothermal reaction on the solution at the temperature of 120-140 ℃, and obtaining Mn after treatment_0.5Cd_0.5S nano-particles;

3) mn obtained in the step 2)_0.5Cd_0.5S nanoparticles and WO obtained in step 1)₃Dispersing the powder in methanol solution for ultrasonic treatment, and then performing circulating reflux at 60-90 ℃ to obtain Mn after treatment_0.5Cd_0.5S/WO₃A complex;

4) mn obtained in the step 3)_0.5Cd_0.5S/WO₃Dispersing the compound in deionized water, then dropwise adding chloroauric acid solution for ultrasonic treatment, then adding sodium borohydride solution, and obtaining Mn after treatment_0.5Cd_0.5S/WO₃Au supported typeA photocatalyst.

3. Mn according to claim 2_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps: the mass ratio of the sodium tungstate to the sodium chloride in the step 1) is 5: 1.

4. Mn according to claim 2_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps: in the step 2), the molar ratio of the cadmium acetate to the manganese acetate is 1: 1.

5. Mn according to claim 2_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps: mn described in step 3)_0.5Cd_0.5S/WO₃The mass ratio is 1: 0.2-0.5.

6. Mn according to claim 2_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps: mn described in step 4)_0.5Cd_0.5S、WO₃The mass ratio of the Au to the Au is 1:0.2-0.5: 0.02-0.05; NaBH₄The molar ratio of the Au to the Au is 5: 1.

7. Mn according to claim 2_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps: in steps 1), 2) and 3), the processing operation is as follows: cooling to room temperature, filtering, washing with water and ethanol, and vacuum drying.

8. Mn according to claim 2_0.5Cd_0.5S/WO₃The preparation method of the Au-supported photocatalyst is characterized by comprising the following steps: in step 4), the processing operation is as follows: filtering and washing with water and ethanol, vacuum drying, and grinding.

9. Mn as set forth in claim 1_0.5Cd_0.5S/WO₃The application of Au supported photocatalyst in photocatalytic hydrogen production.

10. Mn as claimed in claim 9_0.5Cd_0.5S/WO₃The application of the Au-supported photocatalyst in photocatalytic hydrogen production is characterized in that: the operating conditions were, light source: a 300W xenon lamp; amount of catalyst: 0.05 g; concentration of the sacrificial agent: 0.1mol/L of Na₂S and 0.1mol/L of Na₂SO₃。

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