Preparation And Performance Of Metal Phosphide Loading Zinc Zadmium Zulfide Photocatalysis

Hydrogen energy has received growing attention as a renewable and environmental friendly fuel due to the aggravating energy crisis and environmental problems.Semiconductor photocatalytic materials have attracted considerable attention due to their potential application in solving energy conservation,environmental pollution and global warming.The most studied photocatalyst that can use solar photolysis to generate hydrogen is TiO₂.However,TiO₂ has a wide bandgap and can only respond to ultraviolet light,resulting in a low utilization rate of solar energy.The forbidden band width of cadmium zinc sulfide is narrow and can respond under visible light,which greatly improves the utilization of sunlight.Recently,several groups have shown that noble-metal-free materials,can be used as co-catalyst to effectively increase the catalytic performance of photocatalysts.Therefore,we designed three co-catalysts to increase the activity of semiconductors.?1?CoP/Zn0.5Cd0.5SThe CoP was successfully decorated on Zn_0.5Cd_0.5S as a highly efficient co-catalyst via a two-step in-situ chemical deposition method.The chemical and photophysical properties of CoP/Zn0.5Cd0.5S were characterized by XRD,TEM,HRTEM,DRS and XPS.The CoP/Zn_0.5Cd_0.5S composite sample with 5%molar content showed the highest photocatalytic H₂ evolution activity with a corresponding H₂ evolution rate of734?mol·h^-1,which was about 20 times higher than that of pure Zn_0.5Cd_0.5S sample under visible light irradiation.At the same time we proposed a possible photocatalytic mechanism,which can provide a novel concept for the synthesis of other desirable photocatalytic materials with high photocatalytic performance.?2?Ni2P/Zn0.5Cd0.5SNi₂P was successfully decorated on Zn_0.5Cd_0.5S as a highly efficient co-catalyst via a hydrothermal method.At the same time,the morphology,crystal structure,chemical valence,and optical properties of the composite samples were characterized.The photocatalytic H₂ evolution activity and stability of Ni₂P/Zn_0.5Cd_0.5S under visible light irradiation was also characterized.The apparent quantum yield of Ni₂P/Zn_0.5Cd_0.5S for hydrogen production can reach as high as 18.1%at 420 nm.The possible photocatalytic mechanism for enhanced H₂ evolution activity was proposed.?3?Cox Mo1-x S/Zn0.5Cd0.5SCo_x Mo_1-x-x S was successfully decorated on Zn_0.5Cd_0.5S as a highly efficient co-catalyst via a hydrothermal method.At the same time,the morphology,crystal structure,chemical valence,and optical properties of the compo site samples were characterized.The photocatalytic H₂ evolution activity and stability of Co_x Mo_1-x-x S/Zn_0.5Cd_0.5S under visible light irradiation was also characterized.The possible photocatalytic mechanism for enhanced H₂ evolution activity was proposed...