阅读说明：本技术 一种用于光催化醇无氧脱氢的硫化镉材料及制备和应用 (Cadmium sulfide material for anaerobic dehydrogenation of photocatalytic alcohol, and preparation and application thereof ) 是由 王峰 高著衍 罗能超 于 2019-11-13 设计创作，主要内容包括：本发明涉及一种用于光催化醇无氧脱氢的硫化镉材料的制备方法及应用。该方法首先利用溶剂热法制备纳米硫化镉,然后利用离子交换的方法对硫化镉表面进行修饰,最后将金属纳米颗粒原位光沉积负载到修饰的硫化镉材料上,并同时产生氢气。这种方法制得的金属-硫化镉复合催化剂在光催化醇的无氧脱氢反应中具有催化活性高,稳定性好等优势。(The invention relates to a preparation method and application of a cadmium sulfide material for photocatalytic alcohol anaerobic dehydrogenation. The method comprises the steps of firstly preparing nano cadmium sulfide by a solvothermal method, then modifying the surface of the cadmium sulfide by an ion exchange method, finally loading metal nano particles on a modified cadmium sulfide material by in-situ light deposition, and simultaneously generating hydrogen. The metal-cadmium sulfide composite catalyst prepared by the method has the advantages of high catalytic activity, good stability and the like in the anaerobic dehydrogenation reaction of the photocatalytic alcohol.)

1. A preparation method of cadmium sulfide material for anaerobic dehydrogenation of photocatalytic alcohol is characterized by comprising the following steps:

firstly, thermally synthesizing a cadmium sulfide nano material by using cadmium nitrate and thiourea as raw materials under the condition of 120-180 ℃ (preferably 140-160 ℃), wherein the concentration of cadmium ions is 0.01-1 mmol/mL (preferably 0.1-0.5 mmol/mL), and using an ethylenediamine solvent; dispersing the obtained cadmium sulfide in deionized water, adding a metal ion solution, stirring at room temperature for 10-48 h, exchanging metal ions onto the cadmium sulfide in a positive ion form, and adjusting the ion doping amount in the exchanged material by controlling the amount of the added metal ion solution; finally, dispersing the cadmium sulfide after ion exchange in alcohol-containing liquid, adding a metal ion solution, and carrying out in-situ light deposition on the metal on the material in a zero-valent form.

2. The method of claim 1, wherein: the mol ratio of cadmium element to sulfur element in the solvothermal preparation of cadmium sulfide is 1: 1-1: 10, and the heating time is 6-48 hours.

3. The production method according to claim 1 or 2, characterized in that: the mol ratio of cadmium element to sulfur element in the solvothermal preparation of cadmium sulfide is preferably 1: 1-1: 4, and the heating time is preferably 12-36 hours.

4. The method of claim 1, wherein: during ion exchange, the selected ions are one or more of Pt, Pd and Ru, the concentration of the added cadmium sulfide is 1-10 mg/mL, and the mass of the added metal ions is 0.1-1% of that of the cadmium sulfide.

5. The production method according to claim 1 or 4, characterized in that: the concentration of cadmium sulfide added during ion exchange is preferably 2-5 mg/mL, the mass of metal ions added is 0.1-0.5% of that of the cadmium sulfide, and the stirring time at room temperature is preferably 12-24 h.

6. The method of claim 1, wherein: the metal subjected to in-situ photo-deposition is one or more of Pt, Pd, Ru, Rh, Au and Ir, and the mass of the metal is 0.1-2% of that of the ion-exchange cadmium sulfide; the liquid containing alcohol is a mixed system only containing one or more of methanol, ethanol and isopropanol, or one or more of methanol, ethanol and isopropanol and one or more of water, acetonitrile and tetrahydrofuran, and the volume content of one or more of water, acetonitrile and tetrahydrofuran in the mixed system is 1-99%, preferably 10-60%.

7. The production method according to claim 1 or 6, characterized in that: the metal subjected to in-situ light deposition is one or more of Pt, Pd and Ru, and the mass of the metal is 0.1-0.5% of that of the ion exchange cadmium sulfide.

8. A cadmium sulfide material prepared by the preparation method of claims 1-7.

9. Use of the cadmium sulfide material of claim 8 to photocatalytically dehydrogenate an alcohol in the absence of oxygen.

10. Use according to claim 9, characterized in that: the alcohol is one or more of methanol, ethanol and isopropanol, or a mixed system of one or more of methanol, ethanol and isopropanol and one or more of water, acetonitrile and tetrahydrofuran, wherein the volume content of one or more of water, acetonitrile and tetrahydrofuran in the mixed system is 1-99%, preferably 10-60%, and the selected light wavelength is 300-700 nm, preferably 400-550 nm.

Technical Field

The invention belongs to the technical field of material synthesis, and particularly relates to a preparation method and application of a cadmium sulfide material for photocatalytic alcohol anaerobic dehydrogenation.

Background

Cadmium sulfide is a semiconductor sulfide material with excellent visible light absorption, and has wide application in photocatalysis, photoelectrocatalysis, luminescent materials and sensing devices. However, cadmium sulfide is a direct band gap semiconductor, so that the problem of high recombination rate of photo-generated electrons and holes exists when the cadmium sulfide is used as a photocatalyst, and the utilization rate of photo-generated carriers is greatly influenced. In addition, cadmium sulfide in photocatalysis is easily corroded by light, so that the catalyst is seriously deactivated. Therefore, it is one of the major researches of researchers to improve the utilization rate of electron holes in cadmium sulfide and reduce the influence of photo-corrosion.

The cadmium sulfide and other semiconductor materials are compounded to form a heterojunction, which is an important means for improving the photocatalytic performance of the cadmium sulfide. Limited by the influence of interface charges, the band position of the semiconductor, and the like, the choice of semiconductor materials is limited, and commonly used materials are titanium dioxide (CN104646031A), carbon nitride (Applied Catalysis B: Environmental 2019,256,117848), and molybdenum disulfide (nat. Commun.2018,9,1181). The preparation method of the composite material is complex, and the stability of the formed interface heterojunction in the actual reaction is not high.

The solubility of different sulfides is different, and cation exchange can be realized according to the difference of the solubility. The promotion of the photocatalytic performance of cadmium sulfide by precipitating a second sulfide onto cadmium sulfide has been studied before (j.catal.2009,266,165), but no method for adjusting the photocatalytic activity of cadmium sulfide by ion exchange has been reported.

Disclosure of Invention

The invention provides a preparation method and application of a cadmium sulfide material for anaerobic dehydrogenation of photocatalytic alcohol. By carrying out cation exchange on the surface of the cadmium sulfide, the utilization rate of photo-generated carriers of the cadmium sulfide is improved, and the stability of the catalyst is enhanced.

The technical scheme is as follows:

firstly, thermally synthesizing a cadmium sulfide nano material by using cadmium nitrate and thiourea as raw materials under the condition of 120-180 ℃ (preferably 140-160 ℃), wherein the concentration of cadmium ions is 0.01-1 mmol/mL (preferably 0.1-0.5 mmol/mL), and using an ethylenediamine solvent; dispersing the obtained cadmium sulfide in deionized water, adding a metal ion solution, stirring at room temperature for 10-48 h, exchanging metal ions onto the cadmium sulfide in a positive ion form, and adjusting the ion doping amount in the exchanged material by controlling the amount of the added metal ion solution; finally, dispersing the cadmium sulfide after ion exchange in alcohol-containing liquid, adding a metal ion solution, and carrying out in-situ light deposition on the metal on the material in a zero-valent form.

The mol ratio of cadmium element to sulfur element in the solvothermal preparation of cadmium sulfide is 1: 1-1: 10, and the heating time is 6-48 hours.

The mol ratio of cadmium element to sulfur element in the solvothermal preparation of cadmium sulfide is preferably 1: 1-1: 4, and the heating time is preferably 12-36 hours.

During ion exchange, the selected ions are one or more of Pt, Pd and Ru, the concentration of the added cadmium sulfide is 1-10 mg/mL, and the mass of the added metal ions is 0.1-1% of that of the cadmium sulfide.

The concentration of cadmium sulfide added during ion exchange is preferably 2-5 mg/mL, the mass of metal ions added is 0.1-0.5% of that of the cadmium sulfide, and the stirring time at room temperature is preferably 12-24 h.

The metal subjected to in-situ photo-deposition is one or more of Pt, Pd, Ru, Rh, Au and Ir, and the mass of the metal is 0.1-2% of that of the ion-exchange cadmium sulfide; the liquid containing alcohol is a mixed system only containing one or more of methanol, ethanol and isopropanol, or one or more of methanol, ethanol and isopropanol and one or more of water, acetonitrile and tetrahydrofuran, and the volume content of one or more of water, acetonitrile and tetrahydrofuran in the mixed system is 1-99%, preferably 10-60%.

The metal subjected to in-situ light deposition is one or more of Pt, Pd and Ru, and the mass of the metal is 0.1-0.5% of that of the ion exchange cadmium sulfide.

The cadmium sulfide material prepared by the preparation method is used for the anaerobic dehydrogenation of photocatalytic alcohol.

The alcohol is a mixed system containing one or more of methanol, ethanol and isopropanol, or one or more of methanol, ethanol and isopropanol and one or more of water, acetonitrile and tetrahydrofuran, the volume content of one or more of water, acetonitrile and tetrahydrofuran in the mixed system is 1-99%, preferably 10-60%, and the selected light wavelength is 300-700 nm, preferably 400-550 nm.

Compared with other modification methods aiming at cadmium sulfide photocatalyst, the method has the advantages and beneficial effects that:

the preparation method is simple. The doping can be realized by stirring at room temperature by utilizing the difference of solubility products among different sulfides.

Compared with a loading type modification mode, metal ions in the doped cadmium sulfide formed by ion exchange enter a crystal lattice of the cadmium sulfide, contact is tighter, and the metal ions are not easy to lose in subsequent treatment or actual reaction.

The performance can be effectively enhanced by the required metal ion doping amount of less than 0.5 wt%, and the consumption of noble metal is saved.

The invention relates to a preparation method and application of a cadmium sulfide material for photocatalytic alcohol anaerobic dehydrogenation. The metal-cadmium sulfide composite catalyst prepared by the method has the advantages of high catalytic activity, good stability and the like in the anaerobic dehydrogenation reaction of the photocatalytic alcohol.

The specific implementation mode is as follows:

in order to further explain the present invention in detail, several specific embodiments are given below, but the present invention is not limited to these embodiments.

Example 1:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide (rod-shaped, with the diameter of 20-30 nm and the length of 50-100 nm). Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 25.9mL of hydrogen simultaneously.

Example 2:

dissolving 2mmol of cadmium nitrate tetrahydrate and 4mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.21 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 24.0mL of hydrogen simultaneously.

Example 3:

dissolving 2mmol of cadmium nitrate tetrahydrate and 2mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.26 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 22.3mL of hydrogen simultaneously.

Example 4:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 36 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.19 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 21.5mL of hydrogen simultaneously.

Example 5:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.3 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.1 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in a system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on cadmium sulfide, and generating 22mL of hydrogen simultaneously.

Example 6:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 140 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.3 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 18.5mL of hydrogen simultaneously.

Example 7:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on cadmium sulfide, and generating 14.4mL of hydrogen simultaneously.

Example 8:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloroplatinic acid aqueous solution to ensure that the mass of platinum is 0.5 wt% of the mass of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Where platinum is present as a positive ion, the ICP results show an ion-exchanged platinum content of 0.18 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloroauric acid aqueous solution to enable the mass of gold to be 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 4.5mL of hydrogen simultaneously.

Example 9:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloroplatinic acid aqueous solution to ensure that the mass of palladium is 0.5 wt% of the mass of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.11 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in a system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on cadmium sulfide, and generating 16.8mL of hydrogen simultaneously

Example 10:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloroplatinic acid aqueous solution to ensure that the mass of platinum is 0.5 wt% of the mass of cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in a system with argon in a glove box, placing under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on cadmium sulfide, and generating 10.8mL of hydrogen simultaneously.

Example 11:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of ruthenium trichloride aqueous solution to ensure that the mass of ruthenium is 1 wt% of that of cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in a system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on cadmium sulfide, and generating 11.6mL of hydrogen simultaneously.

Example 12:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of ethanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in a system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on cadmium sulfide, and generating 32.1mL of hydrogen simultaneously.

Example 13:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of isopropanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in a system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 44.7mL of hydrogen simultaneously.

Example 14:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. 5mg of ion-exchanged cadmium sulfide was dispersed in 1mL of a mixed solution of methanol and acetonitrile (methanol/acetonitrile volume ratio 1/1), a certain amount of chloropalladate aqueous solution was added so that the mass of palladium was 1 wt% of the mass of cadmium sulfide, oxygen in the solution was removed by ultrasonic treatment, air in the system was replaced with argon gas in a glove box, and then the system was placed under a 455nm LED lamp and irradiated for 10 hours, to reduce the added palladium ions to zero-valent palladium and load the palladium ions on cadmium sulfide, while generating 19.4mL of hydrogen.

Example 14:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of ethanol-tetrahydrofuran mixed solution (ethanol/tetrahydrofuran volume ratio of 1/1), adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of the mass of cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on cadmium sulfide, and generating 16.7mL of hydrogen simultaneously.

Example 15:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide. Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. Dispersing 5mg of ion-exchanged cadmium sulfide in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 2 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing the system under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading the palladium ions on the cadmium sulfide, and generating 23.1mL of hydrogen simultaneously.

Comparative example 1:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide (rod-shaped, with the diameter of 20-30 nm and the length of 50-100 nm). Dispersing 5mg of the cadmium sulfide prepared above in 1mL of methanol solution, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 1 wt% of that of the cadmium sulfide, removing oxygen in the solution by ultrasonic treatment, replacing air in the system with argon in a glove box, placing under a 455nm LED lamp for irradiation for 10 hours, reducing added palladium ions into zero-valent palladium and loading on the cadmium sulfide, and generating 13.2mL of hydrogen simultaneously.

Comparative example 2:

dissolving 2mmol of cadmium nitrate tetrahydrate and 8mmol of thiourea in 20mL of ethylenediamine, transferring the solution to a 50mL hydrothermal kettle with a polytetrafluoroethylene lining, sealing the kettle, and heating the kettle in an oven at 160 ℃ for 20 hours. And then taking out, cooling to room temperature, washing the product with deionized water and ethanol for three times respectively, and drying to obtain bright yellow cadmium sulfide (rod-shaped, with the diameter of 20-30 nm and the length of 50-100 nm). Dispersing 50mg of prepared cadmium sulfide in 50mL of deionized water, adding a certain amount of chloropalladate aqueous solution to ensure that the mass of palladium is 0.5 wt% of that of the cadmium sulfide, stirring at room temperature in a dark place for 12 hours, washing with deionized water and ethanol for three times respectively, and drying to obtain the ion-exchanged cadmium sulfide. Wherein the palladium is present as a positive ion, the ICP results show an ion-exchanged palladium content of 0.23 wt%. 5mg of ion-exchanged cadmium sulfide was dispersed in 1mL of a methanol solution, oxygen in the solution was removed by ultrasonic wave, and after replacing the air in the system with argon gas in a glove box, the system was placed under a 455nm LED lamp and irradiated for 10 hours to generate 1.2mL of hydrogen.