Preparation And Photocatalytic Performance Of Bimetallic Sulfide Modified By Co-catalyst

The rapid development of global economy brings the increasing demand for energy.The reason why human beings have been constantly exploring renewable energy is because fossil fuels are non-renewable.Hydrogen production from the decomposition of water powered by sunlight can realize the transformation from solar energy to chemical energy,which can effectively store solar energy and convert it into clean hydrogen,and this exploration is expected to change the world’s energy landscape.The applications of binary metal sulfides in photocatalysis field are limited due to their low hydrogen-producing activity and strong photocorrosion.Doping other metal ions on the basis of binary metal sulfide can form metal sulfide solid solution,which can achieve the adjustment of the electronic structure and the great improvement of photocatalytic performance.Or we can directly choose ternary bimetallic chalcogenides with appropriate bandgap widths,which when compared with the traditional chalcogenide photocatalytic materials（Cd S）,they also have better photocorrosion resistance.However,bimetallic sulfide still fell into the dilemma of rapid recombination of photogenerated carriers and poor stability in the photocatalytic water decomposition reaction.In order to overcome the above shortcomings,and obtain the photocatalyst with higher performance to explore the application potential of photocatalytic hydrogen production technology in practical production,this paper achieved a significant improvement of photocatalytic performance.Based on Bimetallic sulfides,it can also achieve good stability through the support of noble-metal co-catalyst.Specific research contents were as follows:（1）Mn_0.5Cd_0.5S modified by two dimensional porous Ni₁₂P₅sheets was used for photocatalytic hydrogen production.Uniform Mn_0.5Cd_0.5S nanoparticles and micron-size porous lamellar Ni₁₂P₅were synthesized by simple hydrothermal method.Then the Mn_0.5Cd_0.5S nanoparticles were combined with Ni₁₂P₅tablets by ultrasonic and stirring methods.As a bimetallic sulfide solid solution,Mn_0.5Cd_0.5S had a suitable band gap structure after modulation,which can effectively capture visible light.The two-dimensional porous structure of Ni₁₂P₅not only had a large specific surface area,but also facilitated the exposure of more active sites.In addition,due to the band matching of Ni₁₂P₅and Mn_0.5Cd_0.5S,the efficient migration of photogenerated carriers can be achieved.Therefore,the Ni₁₂P₅/Mn_0.5Cd_0.5S composite showed significantly improved photocatalytic hydrogen production performance and high chemical stability.（2）Ni₃C/Zn In₂S₄nanometer sphere was used for photocatalytic water decomposition to produce hydrogen.Ni₃C nano-spheres were successfully prepared by thermal decomposition of nickel acetate,and then Zn In₂S₄nanospheres were grown in situ on the surface of Ni₃C under mild oil bath conditions.Finally,the Ni₃C/Zn In₂S₄photocatalyst with three-dimensional nano-spheres was obtained.The three-dimensional structure of the composite is beneficial to increase the specific surface area of the material,which has positive significance for light absorption and reaction site.In addition,the in-situ growth of Zn In₂S₄on Ni₃C made the interface of the two semiconductors stay close contact,which can promote the migration of photogenerated carriers,and improve photocatalytic performance of the Ni₃C/Zn In₂S₄composite.