CN115992364B - Antimony-doped tin disulfide electrocatalytic material and preparation method and application thereof - Google Patents

Abstract

The invention provides an antimony doped tin disulfide electrocatalytic material, and a preparation method and application thereof, and belongs to the technical field of electrocatalytic CO ₂ reduction. The invention provides an antimony doped tin disulfide electrocatalytic material, which has a chemical formula of Sb _nSn_1‑nS₂, wherein n=0.005-0.3. According to the invention, in-situ doping of antimony ions is realized, the antimony ions and the tin ions have a synergistic effect, meanwhile, the tin disulfide nanosheets are converted into nano flowers, the specific surface area of the electrocatalyst is increased, more active sites are possessed, and the electrocatalytic carbon dioxide performance of the material is further improved.

Description

Antimony-doped tin disulfide electrocatalytic material and preparation method and application thereof

Technical Field

The present invention relates to the technical field of electrocatalytic _CO2 reduction, and in particular to an antimony-doped tin disulfide electrocatalytic material and a preparation method and application thereof.

Background Art

With the rapid growth of population and the increasing demand for fossil fuels, excessive _CO2 emissions in the atmosphere have led to a series of environmental problems. Therefore, reducing the emission of carbon dioxide in the atmosphere is a major challenge facing today's society.

At present, scientific research has identified several key methods for _CO2 conversion, including biological, chemical, electrochemical, photocatalytic, reforming and inorganic conversion. In contrast, electrocatalytic _CO2 reduction can use renewable energy such as solar energy and wind energy to obtain electricity. Due to its mild reaction conditions, controllable and high efficiency, it has become a research hotspot in the world today. The hydrogen evolution side reaction occurs at the cathode in the cathode chamber and is an inevitable competing reaction in the electrocatalytic _CO2 reduction process. Therefore, a key technical challenge in this process is to develop electrocatalysts with good stability, high selectivity and low reaction overpotential.

The electrocatalytic CO ₂ reduction reaction is a multi-photon electron-coupled transfer process with multiple reaction pathways. Under the action of appropriate electrocatalysts, CO ₂ RR can form a variety of products, including carbon monoxide (CO), methane (CH ₄ ), formic acid (HCOOH), ethylene (C ₂ H ₄ ), ethanol (CH ₃ CH ₂ OH), n-propanol (CH ₃ CH ₂ CH ₂ OH), methanol (CH ₃ OH), etc. Formate is an important hydrogen storage medium that can be used directly as a battery fuel or converted into CO, H ₂ and methanol. It is considered to be cost-effective due to its high market value and relatively low energy input. The introduction of heteroatoms will lead to the hybridization of energy levels between the dopant and the original catalyst, so element doping is an effective method to adjust the electronic structure of the catalyst. For example, Mn-doped In ₂ S ₃ nanosheets can significantly reduce the energy barrier for the activation of CO ₂ to HCOO* compared with undoped In ₂ S ₃ nanosheets.

_SnS2 is an attractive semiconductor material with wide applications in optoelectronic devices, microelectronic devices, biosensors, chemical sensors, electrocatalytic _CO2 reduction, etc. Tin-based compounds are promising electrocatalytic _CO2 reduction catalysts. However, the electrocatalytic _CO2 reduction of pure _SnS2 is accompanied by a strong hydrogen evolution side reaction, which greatly inhibits the electrocatalytic _CO2 reduction performance.

Summary of the invention

In view of this, the object of the present invention is to provide an antimony-doped tin disulfide electrocatalytic material and a preparation method and application thereof. The antimony-doped tin disulfide electrocatalytic material of the present invention has high electrocatalytic CO ₂ reduction performance and activity.

In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

The present invention provides an antimony-doped tin disulfide electrocatalytic material, the general chemical formula of which is Sb _n Sn _1-n S ₂ , wherein n=0.005-0.3.

Preferably, n=0.01-0.02.

Preferably, n=0.01, 0.015 or 0.02.

The present invention also provides a method for preparing the antimony-doped tin disulfide electrocatalytic material described in the above technical solution, comprising the following steps:

Mixing a soluble tin source, a soluble sulfur source, a soluble antimony salt and water to obtain a mixed solution;

The mixed solution is subjected to a hydrothermal reaction to obtain the antimony-doped tin disulfide electrocatalytic material.

Preferably, the temperature of the hydrothermal reaction is 160-200° C., and the time is 4-12 hours.

Preferably, the hydrothermal reaction is carried out in a polytetrafluoroethylene liner.

Preferably, after the hydrothermal reaction, the process further comprises cooling to room temperature, collecting the solid product by centrifugation, washing with water, washing with anhydrous ethanol and drying in sequence to obtain the antimony-doped tin disulfide electrocatalytic material.

Preferably, the drying is vacuum drying, and the temperature of the vacuum drying is 60° C. and the time is 8 hours.

Preferably, the soluble sulfur source comprises thiourea, the soluble tin source comprises tin tetrachloride pentahydrate, and the soluble antimony salt comprises antimony acetate.

The present invention also provides the use of the antimony-doped tin disulfide electrocatalytic material described in the above technical solution or the antimony-doped tin disulfide electrocatalytic material prepared by the preparation method described in the above technical solution in the field of electrocatalytic _CO2 reduction.

The present invention provides an antimony-doped tin disulfide electrocatalytic material, the general chemical formula of which is Sb _n Sn _1-n S ₂ , wherein n=0.005-0.3.

The present invention realizes in-situ doping of antimony ions. Antimony ions and tin ions have a synergistic effect. At the same time, tin disulfide nanosheets are transformed into nanoflowers, which increases the specific surface area of the electrocatalyst, has more active sites, and further improves the electrocatalytic carbon dioxide performance of the material.

The present invention also provides a method for preparing the antimony-doped tin disulfide electrocatalytic material described in the above technical scheme. The present invention adopts a simple hydrothermal method. During the hydrothermal process of synthesizing tin disulfide, an antimony source is added in situ and antimony ions are doped in situ. During the hydrothermal reaction, the tin disulfide nanosheets are transformed into nanoflowers, thereby increasing the specific surface area of the electrocatalyst and thus improving the electrocatalytic carbon dioxide performance of the material.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is the XRD spectrum of Sb _n Sn _1-n S ₂ ;

Figure 2 is the SEM spectra of Sb _n Sn _1-n S ₂ , where (a) is SnS ₂ , (b) is Sb _0.01 Sn _0.99 S ₂ , (c) is Sb _0.015 Sn _0.985 S ₂ , and (d) is Sb _0.02 Sn _0.98 S ₂ ;

FIG3 is a SEM spectrum of the Sb _0.01 Sn _0.99 S ₂ electrocatalyst after electrocatalytic carbon dioxide reduction;

FIG4 is a diagram showing the Faraday efficiency of the electrocatalytic CO ₂ reduction products of the catalysts, wherein (a) is SnS ₂ and (b) is Sb _0.01 Sn _0.99 S ₂ .

DETAILED DESCRIPTION

The present invention provides an antimony-doped tin disulfide electrocatalytic material, the general chemical formula of which is Sb _n Sn _1-n S ₂ , wherein n=0.005-0.3.

In the present invention, the n is preferably 0.01 to 0.02, more preferably 0.01, 0.015 or 0.02.

In the present invention, the antimony-doped tin disulfide electrocatalytic material is in the shape of nanoflowers.

The present invention also provides a method for preparing the antimony-doped tin disulfide electrocatalytic material described in the above technical solution, comprising the following steps:

Mixing a soluble tin source, a soluble sulfur source, a soluble antimony salt and water to obtain a mixed solution;

The mixed solution is subjected to a hydrothermal reaction to obtain the antimony-doped tin disulfide electrocatalytic material.

The invention mixes a soluble tin source, a soluble sulfur source, a soluble antimony salt and water to obtain a mixed solution.

In the present invention, the soluble sulfur source preferably includes thiourea, the soluble tin source preferably includes tin tetrachloride pentahydrate, and the soluble antimony salt preferably includes antimony acetate.

In the present invention, the water is preferably deionized water.

In the present invention, the mixing method is preferably magnetic stirring, and the rotation speed of the magnetic stirring is preferably 400 to 800 r/min.

After obtaining the mixed solution, the present invention performs a hydrothermal reaction on the mixed solution to obtain the antimony-doped tin disulfide electrocatalytic material.

In the present invention, the temperature of the hydrothermal reaction is preferably 160 to 200° C., and the time is preferably 4 to 12 hours.

In the present invention, the hydrothermal reaction is preferably carried out in a polytetrafluoroethylene liner. In the present invention, the polytetrafluoroethylene liner is preferably placed in a blast drying oven for the hydrothermal reaction.

In the present invention, after the hydrothermal reaction, the process preferably further comprises cooling to room temperature, collecting the solid product by centrifugation, washing with water, washing with anhydrous ethanol and drying in sequence to obtain the antimony-doped tin disulfide electrocatalytic material.

In the present invention, the drying is preferably vacuum drying, the temperature of the vacuum drying is preferably 60° C., and the time is preferably 8 hours. In the present invention, the vacuum drying is preferably carried out in a vacuum drying oven.

In the present invention, the water washing and the absolute ethanol washing are preferably performed 3 times.

The present invention also provides the application of the antimony-doped tin disulfide electrocatalytic material described in the above technical solution in the field of electrocatalytic _CO2 reduction.

The present invention has no particular limitation on the specific manner of the application, and any manner familiar to those skilled in the art may be used.

In order to further illustrate the present invention, the antimony-doped tin disulfide electrocatalytic material provided by the present invention and its preparation method and application are described in detail below in conjunction with examples, but they should not be construed as limiting the scope of protection of the present invention.

Comparative Example

Preparation of tin disulfide electrocatalytic materials

Step 1, dissolve 1.28g thiourea and 0.9g tin tetrachloride pentahydrate in 30mL deionized water, stir magnetically at 600r/min for 1 hour, and obtain a mixed solution after complete dissolution;

Step 2, transfer the mixed solution into a polytetrafluoroethylene liner, and put the liner into a reactor, and then put it into a blast drying oven, and heat it at 180° C. for 4 hours. After the reaction is completed, wait for the reactor to cool naturally to room temperature, and collect the solid product by centrifugation;

Step 3, washing the solid product collected by centrifugation with deionized water three times, and then washing it with anhydrous ethanol three times, and collecting the washed solid product by centrifugation;

Step 4: Place the washed solid product in a vacuum oven at 60° C. and dry for 8 hours to obtain a tin disulfide electrocatalytic material, namely SnS ₂ , whose XRD pattern is shown in FIG1 , and SEM pattern is shown in FIG2 (a).

The prepared _SnS2 electrocatalytic material is applied to the method of electrocatalytic reduction of carbon dioxide to formate: an electrolytic cell separated by a proton exchange membrane into an anode tank and a cathode tank is used, the _SnS2 prepared by the above method is used as a working electrode (cathode), a platinum sheet is used as a counter electrode (anode), a saturated calomel electrode is used as a reference electrode (cathode), 0.1 mol/L _KHCO3 electrolyte solution is respectively loaded into the anode tank and the cathode tank, _CO2 is introduced into the cathode tank to a saturated state, and then _CO2 is reduced at a constant potential under the condition of continuous introduction _{of CO2} , the potential control range of the constant potential reduction process is -1.2 to -2.0 V (vsRHE), the SEM image after electrocatalytic carbon dioxide reduction is shown in Figure 3 (a), the Faraday efficiency diagram of the electrocatalytic _CO2 reduction product is shown in Figure 4 (a), and the Faraday efficiency of the electrocatalytic _CO2 reduction to formate at a constant voltage of -1.1 V (vsRHE) is 74%, which is poor performance.

Example 1

The method for preparing antimony-doped tin disulfide electrocatalytic material is carried out according to the following steps:

Step 1, 1.28 g thiourea, 0.9 g tin tetrachloride pentahydrate, and 3.84 mg antimony acetate were dissolved in 30 mL deionized water, and magnetically stirred at 600 r/min for 1 hour to obtain a mixed solution after complete dissolution;

Step 2, transfer the mixed solution into a polytetrafluoroethylene liner, and put the liner into a reactor, and then put it into a blast drying oven, and heat it at 180° C. for 4 hours. After the reaction is completed, wait for the reactor to cool naturally to room temperature, and collect the solid product by centrifugation;

Step 3, washing the solid product collected by centrifugation with deionized water three times, and then washing it with anhydrous ethanol three times, and collecting the washed solid product by centrifugation;

Step 4: Place the washed solid product in a vacuum oven at 60° C. and dry for 8 hours to obtain a tin disulfide electrocatalytic material doped with 0.5% antimony, namely Sb _0.005 Sn _0.995 S ₂ .

The Sb _0.005 Sn _0.995 S ₂ electrocatalytic material prepared by the above method was applied to the electrocatalytic reduction of carbon dioxide to formate, and the method was the same as that of the comparative example. After doping at a constant voltage of -1.1 V (vsRHE), the Faraday efficiency of the electrocatalytic reduction of CO ₂ to formate was 82.57%, and it had good catalytic stability.

Example 2

The method for preparing antimony-doped tin disulfide electrocatalytic material is carried out according to the following steps:

Step 1, 1.28 g thiourea, 0.9 g tin tetrachloride pentahydrate, and 7.67 mg antimony acetate were dissolved in 30 mL deionized water, and magnetically stirred at 600 r/min for 1 hour to obtain a mixed solution after complete dissolution;

Step 2, transfer the mixed solution into a polytetrafluoroethylene liner, and put the liner into a reactor, and then put it into a blast drying oven, and heat it at 180° C. for 4 hours. After the reaction is completed, wait for the reactor to cool naturally to room temperature, and collect the solid product by centrifugation;

Step 3, washing the solid product collected by centrifugation with deionized water three times, and then washing it with anhydrous ethanol three times, and collecting the washed solid product by centrifugation;

Step 4: Place the washed solid product in a 60° C. vacuum oven and dry for 8 hours to obtain a tin disulfide electrocatalytic material doped with 1% antimony, namely Sb _0.01 Sn _0.99 S ₂ , whose XRD pattern is shown in FIG1 , and SEM pattern is shown in FIG2 ( b ).

The Sb _0.01 Sn _0.99 S ₂ electrocatalytic material prepared by the above method was applied to the electrocatalytic reduction of carbon dioxide to formate, and the method was the same as that of the comparative example. The SEM image after electrocatalytic carbon dioxide reduction is shown in Figure 3 (b), and the Faraday efficiency diagram of the electrocatalytic CO ₂ reduction product is shown in Figure 4 (b). After doping at a constant voltage of -1.1 V (vsRHE), the Faraday efficiency of the electrocatalytic reduction of CO ₂ to formate was 90.86%, and it had good catalytic stability.

Example 3

The method for preparing antimony-doped tin disulfide electrocatalytic material is carried out according to the following steps:

Step 1, dissolve 1.28 g thiourea, 0.9 g tin tetrachloride pentahydrate, and 11.51 mg antimony acetate in 30 mL deionized water, stir magnetically at 600 r/min for 1 hour, and obtain a mixed solution after complete dissolution;

Step 2, transfer the mixed solution into a polytetrafluoroethylene liner, and put the liner into a reactor, and then put it into a blast drying oven, and heat it at 180° C. for 4 hours. After the reaction is completed, wait for the reactor to cool naturally to room temperature, and collect the solid product by centrifugation;

Step 3, washing the solid product collected by centrifugation with deionized water three times, and then washing it with anhydrous ethanol three times, and collecting the washed solid product by centrifugation;

Step 4: Place the washed solid product in a 60° C. vacuum oven and dry for 8 hours to obtain a tin disulfide electrocatalytic material doped with 1.5% antimony, namely Sb _0.015 Sn _0.985 S ₂ , whose XRD pattern is shown in FIG1 , and SEM pattern is shown in FIG2 (c).

The Sb _0.015 Sn _0.985 S ₂ electrocatalytic material prepared by the above method was applied to the electrocatalytic reduction of carbon dioxide to formate, and the method was the same as the comparative example. After doping at a constant voltage of -1.1 V (vsRHE), the Faraday efficiency of the electrocatalytic reduction of CO ₂ to formate was 80.23%, and it had good catalytic stability.

Example 4

The method for preparing antimony-doped tin disulfide electrocatalytic material is carried out according to the following steps:

Step 1, 1.28 g thiourea, 0.9 g tin tetrachloride pentahydrate, and 15.35 mg antimony acetate were dissolved in 30 mL deionized water, and magnetically stirred at 600 r/min for 1 hour to obtain a mixed solution after complete dissolution;

Step 2, transfer the mixed solution into a polytetrafluoroethylene liner, and put the liner into a reactor, and then put it into a blast drying oven, and heat it at 180° C. for 4 hours. After the reaction is completed, wait for the reactor to cool naturally to room temperature, and collect the solid product by centrifugation;

Step 3, washing the solid product collected by centrifugation with deionized water three times, and then washing it with anhydrous ethanol three times, and collecting the washed solid product by centrifugation;

Step 4: Place the washed solid product in a 60° C. vacuum oven and dry for 8 hours to obtain a tin disulfide electrocatalytic material doped with 2% antimony, namely Sb _0.02 Sn _0.98 S ₂ , whose XRD pattern is shown in FIG1 , and SEM pattern is shown in FIG2 (d).

The Sb _0.02 Sn _0.98 S ₂ electrocatalytic material prepared by the above method was applied to the electrocatalytic reduction of carbon dioxide to formate, and the method was the same as the comparative example. After doping at a constant voltage of -1.1 V (vsRHE), the Faraday efficiency of the electrocatalytic reduction of CO ₂ to formate was 80.84%, and it had good catalytic stability.

Example 5

The method for preparing antimony-doped tin disulfide electrocatalytic material is carried out according to the following steps:

Step 1, 1.28 g thiourea, 0.9 g tin tetrachloride pentahydrate, and 230.1 mg antimony acetate were dissolved in 30 mL deionized water, and magnetically stirred at 600 r/min for 1 hour to obtain a mixed solution after complete dissolution;

Step 2, transfer the mixed solution into a polytetrafluoroethylene liner, and put the liner into a reactor, and then put it into a blast drying oven, and heat it at 180° C. for 4 hours. After the reaction is completed, wait for the reactor to cool naturally to room temperature, and collect the solid product by centrifugation;

Step 3, washing the solid product collected by centrifugation with deionized water three times, and then washing it with anhydrous ethanol three times, and collecting the washed solid product by centrifugation;

Step 4: Place the washed solid product in a vacuum oven at 60° C. and dry for 8 hours to obtain a tin disulfide electrocatalytic material doped with 30% antimony, namely Sb _0.3 Sn _0.7 S ₂ .

The Sb _0.3 Sn _0.7 S ₂ electrocatalytic material prepared by the above method was applied to the electrocatalytic reduction of carbon dioxide to formate, and the method was the same as the comparative example. After doping at a constant voltage of -1.1 V (vsRHE), the Faraday efficiency of the electrocatalytic reduction of CO ₂ to formate was 68.41%, and it had good catalytic stability.

The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims (8)

1. An antimony-doped tin disulfide electrocatalytic material, characterized in that the general chemical formula is _{SbnSn1 -nS2 ,} wherein n=0.01, 0.015 or 0.02. 2. The method for preparing the antimony-doped tin disulfide electrocatalytic material according to claim 1, characterized in that it comprises the following steps: Mixing a soluble tin source, a soluble sulfur source, a soluble antimony salt and water to obtain a mixed solution; The mixed solution is subjected to a hydrothermal reaction to obtain the antimony-doped tin disulfide electrocatalytic material. 3. The preparation method according to claim 2 is characterized in that the temperature of the hydrothermal reaction is 160-200°C and the time is 4-12 hours. 4. The preparation method according to claim 2 or 3, characterized in that the hydrothermal reaction is carried out in a polytetrafluoroethylene liner. 5. The preparation method according to claim 4 is characterized in that after the hydrothermal reaction, it also includes cooling to room temperature, centrifuging to collect solid products, washing with water, washing with anhydrous ethanol and drying in sequence to obtain the antimony-doped tin disulfide electrocatalytic material. 6 . The preparation method according to claim 5 , characterized in that the drying is vacuum drying, the temperature of the vacuum drying is 60° C., and the time is 8 hours. 7. The preparation method according to claim 2, characterized in that the soluble sulfur source comprises thiourea, the soluble tin source comprises tin tetrachloride pentahydrate, and the soluble antimony salt comprises antimony acetate. 8. Use of the antimony-doped tin disulfide electrocatalytic material according to claim 1 or the antimony-doped tin disulfide electrocatalytic material prepared by the preparation method according to any one of claims 2 to 7 in the field of electrocatalytic _CO2 reduction.