Preparation Of High-Efficiency Organic-Inorganic Perovskite Composite Photocatalysts For Hydrogen Production

Converting solar energy into clean and high-energy hydrogen energy through photocatalytic technology is a reliable way to deal with the current energy crisis.At present,an important challenge in photocatalytic technology is the problem of charge recombination.The introduction of cocatalysts can accelerate electron transfer and improve optoelectronic properties,which is one of the more commonly used strategies to enhance photocatalytic activity.In this paper,different states of promoters were introduced to construct two composite photocatalysts based on MAPb I₃,using the excellent electron transfer ability of the promoters to optimize the photocatalytic HER performance.The main findings are as follows:（1）Amorphous Ni Co B was loaded on the surface of MAPb I₃ crystallites by electrostatic self-assembly method to prepare the Ni Co B/MAPb I₃ composite,which was applied in the photolysis of HI for hydrogen production.The experimental results show that the highest hydrogen production rate is 2625.57μmol g^-1 h^-1 when the loading ratio is 30 wt%,which is114 times that of pure MAPb I₃,and the hydrogen evolution is stable within 24 h.Various characterization tests indicate that the energy band position of amorphous Ni Co B matches that of MAPb I₃,and itself can act as an electron capture and proton adsorption center,so that electrons in MAPb I₃ are transferred to Ni Co B along the interface,and effective charge separation is achieved,which greatly promotes H₂ release.（2）1T-WS₂ nanosheets were prepared by a hydrothermal method and combined with MAPb I₃ to form a 1T-WS₂/MAPb I₃ composite for photocatalytic splitting HI into H₂.The HER results show that the optimal hydrogen production rate can reach 2806.60μmol g^-1 h^-1,which is nearly 95 times higher than that of the monomer,and can maintain the stability for36 h.Benefiting from the low Fermi level,strong conductivity,and abundant active sites on the basal plane of 1T-WS₂,the charge transfer resistance of the 1T-WS₂/MAPb I₃ complex is greatly reduced,and electrons can be rapidly transferred to 1T-WS₂ to achieve the reduction of H⁺.