Noble metal-free core-shell CdS/iron phthalocyanine Z-scheme photocatalyst for enhancing photocatalytic hydrogen evolution

摘要

Improving the separation efficiency of photogenerated carriers and broadening the light absorption range of the photocatalyst are two important factors for improving the performance of the photocatalyst.In this paper,a new and efficient Z-scheme Cd S/iron phthalocyanine(Cd S/Fe Pc)core-shell nanostructure composite material is prepared by a simple solid-phase reaction method.There are two key points in the preparation of composite materials:one is that hydrogen bonding energy is closely connected with Fe Pc,another is that Fe Pc can be uniformly assembled on Cd S nanoparticles.The photocatalytic hydrogen evolution(PHE)of the Cd S/Fe Pc nanocomposite(73.01μmol/h)is 2.6 times higher than that of pure Cd S(26.67μmol/h).In addition,after 4 photocatalytic cycles,the PHE of the Cd S/Fe Pc composite is still 92.3%of the first cycle.There are three reasons for this situation:(1)The Z-scheme heterojunction is formed to improve the separation efficiency of photogenerated carriers;(2)Fe Pc expands the visible light absorption range of Cd S;(3)The large core-shell contact area is favorable for the separation of photo-induced carriers at the interfaces.This research is conducive to the further development of new photocatalytic materials with high efficiency,low cost and simple preparation.