Synthesis And Photocatalytic Hydrogen Evolution Of CdS-Ni/MIL-101(Cr) And Pt-Ni/CdS

The difficult situation of energy depletion and environmental pollution are aggravating needing to mitigate urgently.It is very important to find a new alternative green energy.Photochemical water splitting is generally considered as a good way to get alternative renewable energy source because there is plenty of solar light,and it is environment-friendly.To date,most photocatalytic materials are oxides,sulfides,composites and so on.However,absorbing and utilizing sunlight energy more efficiently is still an unsolved problem in hydrogen production.Metal-organic frameworks materials?MOFs?have attracted a great deal of attention due to their high specific surface area,controlled pore size and diverse structures.However,its application is very limited in the field of photocatalytic hydrogen production,and the hydrogen production efficiency of MOFs is very low.Based on the research of our research group,in this paper transition metal Ni was doped on MIL-101?Cr?carrier and CdS-Ni/MIL-101?Cr?was successfully synthesized.Moreover,the material Pt-Ni/CdS was also successfully prepared.Until now,no studies have been reported on the use of these two materials for photocatalytic hydrogen production.These materials can more effectively absorb the energy of solar light,compared with pure CdS and MOFs,which greatly enhanced the efficiency of photocatalytic hydrogen production.The main contents of this paper include:Ni/MIL-101?Cr?was prepared by hydrothermal method and then CdS was loaded on MIL-101?Cr?by solvothermal method.Pt-Ni/CdS materials were also prepared by solvothermal method.The materials were characterized by powder X ray diffraction,scanning electron microscope,N₂ adsorption/desorption,transmission electron microscope and so on.The results of these materials used in photocatalytic hydrogen production implied that the hydrogen production activity of the materials increased obviously after doped with Ni.The highest hydrogen production rate of 10%CdS-1%Ni/MIL-101?Cr?is 0.41mmol/?g·h?,which is 10 times higher than the materials without Ni.Moreover,the highest hydrogen production rate of 0.1%Pt-2%Ni/CdS is up to 4.78 mmol/?g·h?,which is 40 times higher than that of pure CdS,and 4.8 times higher than that of Pt/CdS.In this paper,two series of materials modified by transition metal Ni were successfully prepared.The doping of transition metal Ni improves the pore structure and the specific surface area of CdS-Ni/MIL-101?Cr?and Pt-Ni/CdS materials.In addition,these materials are not easily corroded by solar light with higher photocatalytic hydrogen production stability.Pt-Ni/CdS materials can be easily prepared and exhibited great hydrogen production activity compared with another one.Ni/MIL-101?Cr?itself has no ability to produce hydrogen by photocatalysis,while it has the photocatalytic activity of producing H₂ after loading CdS.In conclusion,transition metal Ni has great synergistic effect with CdS enhancing the absorption of light and consequently increasing the hydrogen production activity of CdS-Ni/MIL-101?Cr?and Pt-Ni/CdS materials.