BiVO4/Co1-XPreparation method and application of S composite photoelectrode
1. BiVO4/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps:
A. to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, and then adjusting the pH value to 1.7 by using concentrated nitric acid, namely a solution A; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dropwise adding a vanadium source on the surface of the BiOI film, and calcining at 300-550 ℃ for 1-4 h to obtain BiVO4A film;
B. 50 mL of deionized water is added into the four beakers respectively, the numbers of the four beakers are 1, 2, 3 and 4, and 0.05-0.15 mmol of Co (NO) is dissolved in the No. 1 beaker3)2·6H2O, dissolving 0.05 to 0.15 mmol of Na in No. 3 beaker2S；
C. Will be loaded with BiVO4The FTO sheets are soaked in the beakers according to the numbering sequence, taken out after circulating for 10-50 times, washed by deionized water and dried at room temperature to obtain BiVO4/Co1-XS。
2. BiVO according to claim 14/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps: step A, after a vanadium source is dripped on the surface of the mixture, calcining the mixture for 2 hours at 450 ℃ to obtain BiVO4A film.
3. The method of claim 1BiVO4/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps: and B, cleaning the surface of the cleaned FTO glass sheet, respectively ultrasonically cleaning the FTO glass sheet in acetone, isopropanol and ethylene glycol for 0.5 h, taking out and airing.
4. BiVO according to claim 14/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps: and step A, performing electrodeposition, namely connecting the prepared sample serving as a working electrode, Ag/AgCl and Pt serving as a reference electrode and a counter electrode respectively with an electrochemical workstation, and setting the bias voltage to be minus 0.1V vs. Ag/AgCl for 5 min.
5. BiVO according to claim 14/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps: and the vanadium source in the step A is dimethyl sulfoxide solution containing 0.2M vanadyl acetylacetonate.
6. BiVO according to claim 14/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps: step B dissolving 0.1mmol Co (NO) in No. 1 beaker3)2·6H2O。
7. BiVO according to claim 14/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps: step B dissolving 0.1mmol of Na in No. 3 beaker2S。
8. BiVO according to claim 14/Co1-XThe preparation method of the S composite photoelectrode is characterized by comprising the following steps: step C said will load BiVO4The FTO sheets are soaked in the beakers according to the numbering sequence, and are taken out after 30 times of circulation.
9. BiVO prepared by the method of any one of claims 1 to 84/Co1-XThe S composite photoelectrode is characterized in that: BiVO in the composite photoelectrode4Exhibit a worm-like shapeStructure, composite Co1-XAfter S, BiVO4The surface has distinct nanoparticles.
10. BiVO according to claim 94/Co1-XThe application of the S composite photoelectrode is characterized in that: the method is applied to photoelectrocatalysis decomposition of water to prepare hydrogen.
Background
H2As an ideal energy carrier, the composite material can be used in the fields of energy storage, transportation, fuel cells and the like. H2The energy provided in the combustion process is far higher than that of fossil fuel, the combustion product does not cause pollution to the environment, and the energy is one of important energy sources capable of replacing the fossil fuel, so that clean and efficient H is explored2The energy production mode is necessary to effectively promote the green sustainable development. Solar-driven hydrogen production by water splitting is an environmentally friendly process, where Photoelectrochemical (PEC) splitting of water is a mature and promising technology. However, in the PEC system, the performance impact of screening for suitable semiconductors is important, BiVO4There has been much interest in this area. BiVO4With a suitable band gap (2.4 eV), the conduction band is very close to H+/H2Thermodynamic redox potential of the reaction, which is responsible for the decomposition of water to produce H2Has obvious advantages and BiVO4The conversion efficiency of solar energy to hydrogen can be promoted to reach 9.3%. Furthermore, BiVO4Has the advantages of stable performance, low toxicity, excellent visible light response and the like.
However, BiVO is greatly limited by problems of slow carrier transport speed and oxidation kinetics, high electron-hole recombination efficiency, and the like4The use of (1). Researchers have tried many ways to solve these problems, such as element doping, heterojunction construction, synthesis of oxygen vacancies, etc., with great success. For example, by Ar-plasma etchingTechnique, BiVO4The film can generate controllable oxygen vacancy, and the photocurrent reaches 4.32 mA/cm2Is far higher than other pure BiVO4. This is primarily due to the activation of surface oxygen vacancies to facilitate charge separation and transfer to the water oxidation reaction. In addition to the above-mentioned method, the modification with cocatalyst can also raise BiVO4General method of Performance. Transition metal compounds are generally used as Oxygen Evolution Reaction (OER) catalysts, and transition metal sulfides, for example, have the advantages of low cost, high thermal stability, weak M-S bond, and no toxicity, and are called ideal anode materials. It is noteworthy that transition metal sulfides have high electrical conductivity, since the low electronegativity of sulfur makes it react with metals to form elastic structures, which is very advantageous for the transport of electrons. Wherein Co1-XS is a semiconductor material with a narrow band gap (1.25 eV), which reacts with BiVO4The energy band structures of the two-dimensional light-emitting diode are matched, and the two-dimensional light-emitting diode has strong visible light absorption capacity. Thus, Co1-XS and BiVO4The combination of (a) will effectively separate the photogenerated electron-hole pairs, thereby improving PEC performance.
So far, there is no disclosure of successful application of BiVO by SILAR method4And Co1-XS is compounded and used for photoelectrochemical water decomposition.
Disclosure of Invention
In order to solve BiVO4The invention discloses a Co-based organic electroluminescent device and a preparation method thereof, and solves the problems of low electron hole transmission speed, high recombination rate and slow interface reaction kinetics of a semiconductor1-XS modified BiVO4Semiconductor (BiVO)4/Co1-XS) preparation method.
The technical scheme is as follows:
potassium iodide, concentrated nitric acid and bismuth nitrate pentahydrate (Bi (NO)3)3·5H2O), p-benzoquinone and FTO glass sheets are used as raw materials, a BiOI film is obtained on the surface of the FTO by an electrodeposition method, and then the BiVO is synthesized by calcination treatment and SILAR4/Co1-XS。
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: adding into 50 mL deionized water3.32 g KI and 0.97 g Bi (NO)3)3∙5H2O, stirring and dissolving, and then adjusting the pH value to 1.7 by using concentrated nitric acid, namely a solution A; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, and calcining at 300-550 ℃ for 1-4 h, preferably at 450 ℃ for 2 h after a vanadium source is dripped on the surface of the BiOI film to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: 50 mL of deionized water is added into the four beakers respectively, the numbers of the four beakers are 1, 2, 3 and 4, and 0.05-0.15 mmol of Co (NO) is dissolved in the No. 1 beaker3)2·6H2O, preferably 0.1mmol, and 0.05 to 0.15 mmol of Na dissolved in No. 3 beaker2S, preferably 0.1 mmol;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheets are soaked in the beakers according to the numbering sequence, are taken out after circulating for 10-50 times, preferably 30 times, are washed by deionized water and are dried at room temperature to obtain BiVO4/Co1-XS。
In the preferred embodiment of the invention, the cleaned FTO glass sheet in step a is prepared by cleaning the surface of the FTO glass sheet, ultrasonic cleaning the FTO glass sheet in acetone, isopropanol and ethylene glycol for 0.5 h, taking out, and air drying.
In the preferred embodiment of the invention, in the step A, the prepared sample is taken as a working electrode, Ag/AgCl and Pt are respectively taken as a reference electrode and a counter electrode, the working electrode and the counter electrode are connected with an electrochemical workstation, the bias voltage is set to be-0.1V vs. Ag/AgCl, and the time is 5 min.
In a preferred embodiment of the invention, the vanadium source in step A is a dimethyl sulfoxide solution containing 0.2M vanadyl acetylacetonate.
BiVO prepared according to the method disclosed by the invention4/Co1-XS，BiVO4Exhibiting a worm-like structure, complex Co1-XAfter S, BiVO4The surface has distinct nanoparticles.
Another purpose of the invention is to discloseBiVO4/Co1-XAnd S, applying to photoelectrocatalysis water decomposition hydrogen production.
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution is prepared, and the concentration of the solution is 0.1-1.0 mol.L-1Na of (2)2SO4The solution is placed in the dark, preferably 0.5 mol.L-1；
(2) The BiVO treated by different soaking times4/Co1-XS samples are respectively placed in a photoelectrocatalysis device, and prepared Na is added2SO4And (5) turning on a light source to perform a hydrogen production experiment by photoelectrocatalysis water decomposition.
The invention has the characteristics that:
(1) introduction of Co1-XS forms BiVO4/Co1-XThe S-shaped photoelectrode effectively promotes carrier migration and inhibits electron hole pair recombination;
(2) introduction of Co1-XS forms BiVO4/Co1-XThe S photoelectrode enables the photoelectrocatalysis to decompose water to achieve higher hydrogen production efficiency.
BiVO prepared by the invention4/Co1-XThe S-shaped photoelectrode utilizes instruments such as X-ray diffraction (XRD), a Scanning Electron Microscope (SEM), X-ray photoelectron spectroscopy (XPS) and the like to analyze the appearance structure and the composition of a product, an ultraviolet-visible spectrophotometer is used for measuring absorbance, and a standard three-electrode electrochemical workstation is used for measuring transient photocurrent and stability so as to evaluate the photoelectrocatalysis activity of the S-shaped photoelectrode.
The reagent used in the invention is commercially available.
Advantageous effects
The invention utilizes an electrodeposition method, a calcination method and an SILAR method to synthesize BiVO4/Co1-XS，Co1-XS nano-particles are compounded in BiVO4Effectively improve BiVO on the surface4/Co1-XThe S composite photoelectric catalyst has carrier migration rate, improves the problem of electron and hole recombination, and improves the photoelectric catalytic performance. The preparation process is simple, and the prepared BiVO4/Co1-XThe S has good application prospect in preparing hydrogen by photoelectrocatalysis water decomposition, and can be used in the fields of environment, energy and the likeHas the function of the medicine.
Drawings
FIG. 1. BiVO prepared in example 14/Co1-XXRD diffraction spectrum of S photoelectrode;
FIG. 2 BiVO prepared in example 14/Co1-XXPS plot of S photoelectrode;
FIG. 3 BiVO prepared in example 14/Co1-XA Scanning Electron Microscope (SEM) image of the S-photo electrode;
FIG. 4 BiVO prepared in example 14/Co1-XA UV-vis spectrogram of an S-ray electrode;
FIG. 5 BiVO prepared in example 14/Co1-XA Linear Sweep Voltammetry (LSV) plot of the S-ray electrode;
FIG. 6 BiVO prepared in example 14/Co1-XStability (i-t) diagram of S-photoelectrode.
Detailed Description
The present invention will be described in detail below with reference to examples to enable those skilled in the art to better understand the present invention, but the present invention is not limited to the following examples.
The surfaces of the FTO glass sheets used in the following examples were cleaned, then ultrasonically cleaned in acetone, isopropanol and ethylene glycol for 0.5 h, removed and dried.
The electrodeposition process conditions are that a prepared sample is taken as a working electrode, Ag/AgCl and Pt are respectively taken as a reference electrode and a counter electrode, the reference electrode and the counter electrode are connected with an electrochemical workstation, the bias voltage is set to be-0.1V vs. Ag/AgCl, and the time is 5 min.
Example 1
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, then adjusting the pH value to 1.7 by using concentrated nitric acid, and naming the solution as A solution; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and stirring uniformly to obtain a precursorA bulk solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dripping a vanadium source on the surface of the BiOI film, and calcining for 2 hours at 450 ℃ in a muffle furnace to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: four 50 mL beakers were prepared, numbered 1, 2, 3, and 4, respectively. In a No. 1 beaker, 0.1mmol Co (NO)3)2·6H2O was dissolved in 50 mL of deionized water, and 0.1mmol of Na was added to No. 3 beaker2S to 50 mL of aqueous solution, the beakers 2 and 4 are pure deionized water;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheet is soaked in four beakers containing different solutions in turn, namely the SILAR method, the FTO sheet is taken out after 30 times of circulation, washed by deionized water and dried at room temperature to obtain BiVO4/Co1-XS。
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution was prepared at a concentration of 0.5 mol. L-1Na of (2)2SO4A solution;
(2) taking BiVO with different soaking times4/Co1-XS samples are respectively placed in a photoelectrocatalysis device, and prepared Na is added2SO4And (5) turning on a light source to perform a hydrogen production experiment by photoelectrocatalysis water decomposition.
BiVO4/Co1-XCharacterization of S-ray electrode
As shown in FIG. 1, Co1-XS nanoparticle loaded BiVO4The XRD patterns before and after the detection show that Co is not found1-XThe characteristic peak of S is due to low content;
as shown in FIG. 2, the XPS chart containing the existence of Bi, O, V, S and Co elements and corresponding valence states proves that Co is effectively prepared1-XS；
BiVO as shown in FIG. 34Vermicular morphology of and Co1-XS nano-particles are uniformly attached to BiVO4A surface;
as shown in fig. 4, pure BiVO4And BiVO4/Co1-XS shows a steeper absorption edge at 510 nm, BiVO4/Co1-XS-ray electrode is arranged onThe absorbance in the visible light area is improved to a certain extent;
BiVO, as shown in FIG. 54/Co1-XLinear Sweep Voltammetry (LSV) testing of S-photoelectrode maximum photocurrent of 2.9 mA/cm at different soak times treatments2（1.23 V vs RHE）；
BiVO, as shown in FIG. 64/Co1-XThe S-shaped photoelectrode has good stability.
Example 2
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, then adjusting the pH value to 1.7 by using concentrated nitric acid, and naming the solution as A solution; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dripping a vanadium source on the surface of the BiOI film, and calcining for 3 hours at 350 ℃ in a muffle furnace to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: four 50 mL beakers were prepared, numbered 1, 2, 3, and 4, respectively. In a No. 1 beaker, 0.05 mmol Co (NO)3)2·6H2O was dissolved in 50 mL of deionized water, and 0.05 mmol of Na was added to No. 3 beaker2S to 50 mL of aqueous solution, the beakers 2 and 4 are pure deionized water;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheet is soaked in four beakers containing different solutions in turn, namely the SILAR method, the FTO sheet is taken out after 10 times of circulation, washed by deionized water and dried at room temperature to obtain BiVO4/Co1-XS。
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution was prepared at a concentration of 0.5 mol. L-1Na of (2)2SO4A solution;
(2) taking BiVO with different soaking times4/Co1-XS samples are respectively placed in a photoelectrocatalysis device, and prepared Na is added2SO4And (5) turning on a light source to perform a hydrogen production experiment by photoelectrocatalysis water decomposition.
BiVO4/Co1-XMaximum photocurrent of 1.79 mA/cm for Linear Sweep Voltammetry (LSV) test of S-photo electrode2（1.23 V vs RHE）。
Example 3
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, then adjusting the pH value to 1.7 by using concentrated nitric acid, and naming the solution as A solution; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dripping a vanadium source on the surface of the BiOI film, and calcining for 2 hours at 350 ℃ in a muffle furnace to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: four 50 mL beakers were prepared, numbered 1, 2, 3, and 4, respectively. In a No. 1 beaker, 0.15 mmol Co (NO)3)2·6H2O was dissolved in 50 mL of deionized water, and 0.15 mmol of Na was added to No. 3 beaker2S to 50 mL of aqueous solution, the beakers 2 and 4 are pure deionized water;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheet is soaked in four beakers containing different solutions in turn, namely the SILAR method, the FTO sheet is taken out after circulating for 20 times, is washed by deionized water and is dried at room temperature, and BiVO can be obtained4/Co1-XS。
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution was prepared at a concentration of 0.5 mol. L-1Na of (2)2SO4A solution;
(2) taking BiVO with different soaking times4/Co1-XS samples, respectively placed in photoelectricityAdding prepared Na into a catalytic device2SO4And (5) turning on a light source to perform a hydrogen production experiment by photoelectrocatalysis water decomposition.
BiVO4/Co1-XMaximum photocurrent of 1.95 mA/cm for Linear Sweep Voltammetry (LSV) test of S-photo electrode2（1.23 V vs RHE）。
Example 4
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, then adjusting the pH value to 1.7 by using concentrated nitric acid, and naming the solution as A solution; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dripping a vanadium source on the surface of the BiOI film, and calcining for 3 hours at 450 ℃ in a muffle furnace to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: four 50 mL beakers were prepared, numbered 1, 2, 3, and 4, respectively. In a No. 1 beaker, 0.1mmol Co (NO)3)2·6H2O was dissolved in 50 mL of deionized water, and 0.1mmol of Na was added to No. 3 beaker2S to 50 mL of aqueous solution, the beakers 2 and 4 are pure deionized water;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheet is soaked in four beakers containing different solutions in turn, namely the SILAR method, the FTO sheet is taken out after circulating for 40 times, is washed by deionized water and is dried at room temperature, and BiVO can be obtained4/Co1-XS。
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution was prepared at a concentration of 0.5 mol. L-1Na of (2)2SO4A solution;
(2) taking BiVO with different soaking times4/Co1-XS samples are respectively placed in a photoelectrocatalysis device, and prepared Na is added2SO4And (5) turning on a light source to perform a hydrogen production experiment by photoelectrocatalysis water decomposition.
BiVO4/Co1-XMaximum photocurrent of 2.06 mA/cm for Linear Sweep Voltammetry (LSV) test of S-photo electrode2（1.23 V vs RHE）。
Example 5
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, then adjusting the pH value to 1.7 by using concentrated nitric acid, and naming the solution as A solution; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dripping a vanadium source on the surface of the BiOI film, and calcining for 4 hours at 350 ℃ in a muffle furnace to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: four 50 mL beakers were prepared, numbered 1, 2, 3, and 4, respectively. In a No. 1 beaker, 0.05 mmol Co (NO)3)2·6H2O was dissolved in 50 mL of deionized water, and 0.05 mmol of Na was added to No. 3 beaker2S to 50 mL of aqueous solution, the beakers 2 and 4 are pure deionized water;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheet is soaked in four beakers containing different solutions in turn, namely the SILAR method, the FTO sheet is taken out after circulating for 50 times, is washed by deionized water and is dried at room temperature, and BiVO can be obtained4/Co1-XS。
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution was prepared at a concentration of 0.5 mol. L-1Na of (2)2SO4A solution;
(2) taking BiVO with different soaking times4/Co1-XS samples are respectively placed in a photoelectrocatalysis device, and prepared Na is added2SO4Solution, openingAnd (4) carrying out a hydrogen production experiment by decomposing water through photoelectrocatalysis by using a light source.
BiVO4/Co1-XMaximum photocurrent of 1.94 mA/cm for Linear Sweep Voltammetry (LSV) test of S-photo electrode2（1.23 V vs RHE）。
Example 6
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, then adjusting the pH value to 1.7 by using concentrated nitric acid, and naming the solution as A solution; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dripping a vanadium source on the surface of the BiOI film, and calcining for 1 h at 550 ℃ in a muffle furnace to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: four 50 mL beakers were prepared, numbered 1, 2, 3, and 4, respectively. In a No. 1 beaker, 0.15 mmol Co (NO)3)2·6H2O was dissolved in 50 mL of deionized water, and 0.15 mmol of Na was added to No. 3 beaker2S to 50 mL of aqueous solution, the beakers 2 and 4 are pure deionized water;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheet is soaked in four beakers containing different solutions in turn, namely the SILAR method, the FTO sheet is taken out after 10 times of circulation, washed by deionized water and dried at room temperature to obtain BiVO4/Co1-XS。
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution was prepared at a concentration of 0.5 mol. L-1Na of (2)2SO4A solution;
(2) taking BiVO with different soaking times4/Co1-XS samples are respectively placed in a photoelectrocatalysis device, and prepared Na is added2SO4The solution is prepared by opening the light source and performing photoelectrocatalysis water decompositionAnd (5) hydrogen experiment.
BiVO4/Co1-XMaximum photocurrent of 2.32 mA/cm for Linear Sweep Voltammetry (LSV) test of S-photo electrode2（1.23 V vs RHE）。
Example 7
BiVO4/Co1-XThe preparation method of the S composite photoelectrode comprises the following steps:
A、BiVO4preparing a film: to 50 mL of deionized water were added 3.32 g of KI and 0.97 g of Bi (NO)3)3∙5H2O, stirring and dissolving, then adjusting the pH value to 1.7 by using concentrated nitric acid, and naming the solution as A solution; 0.4968 g of p-benzoquinone is added into 20 mL of ethanol and stirred until the p-benzoquinone is dissolved, and the solution is named as solution B; mixing the solution A and the solution B, and uniformly stirring to obtain a precursor solution; electrodepositing on the surface of cleaned FTO to obtain a BiOI film, dripping a vanadium source on the surface of the BiOI film, and calcining for 2 hours at 550 ℃ in a muffle furnace to obtain BiVO4A film;
B、Co1-Xpreparing an S precursor solution: four 50 mL beakers were prepared, numbered 1, 2, 3, and 4, respectively. In a No. 1 beaker, 0.1mmol Co (NO)3)2·6H2O was dissolved in 50 mL of deionized water, and 0.1mmol of Na was added to No. 3 beaker2S to 50 mL of aqueous solution, the beakers 2 and 4 are pure deionized water;
C、BiVO4/Co1-Xs preparation: will be loaded with BiVO4The FTO sheet is soaked in four beakers containing different solutions in turn, namely the SILAR method, the FTO sheet is taken out after circulating for 20 times, is washed by deionized water and is dried at room temperature, and BiVO can be obtained4/Co1-XS。
Experiment for photoelectrocatalysis water decomposition
(1) 50 mL of the solution was prepared at a concentration of 0.5 mol. L-1Na of (2)2SO4A solution;
(2) taking BiVO with different soaking times4/Co1-XS samples are respectively placed in a photoelectrocatalysis device, and prepared Na is added2SO4And (5) turning on a light source to perform a hydrogen production experiment by photoelectrocatalysis water decomposition.
BiVO4/Co1-XMaximum photocurrent of 2.41 mA/cm for Linear Sweep Voltammetry (LSV) test of S-photo electrode2（1.23 V vs RHE）。
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present invention or directly or indirectly applied to other related technical fields are included in the scope of the present invention.
