A novel Ni0.85Se/MoSSe heterojunction demonstrated omnipotent boosting catalytic ability in photocatalysis, photoelectrochemistry and electrocatalysis

Abstract

A new type II 0D/3D Ni0.85Se/MoSSe heterojunction photocatalyst was prepared via a hydrothermal method. These Ni0.85Se/MoSSe heterojunction photocatalysts exhibited outstanding catalytic performance in photocatalysis, electrocatalysis and photoelectrochemistry. By optimizing the composited ratio of MoSSe, the catalyst showed a photocurrent density of 32.95 μA/cm2 which was 4.23 and 32.95 times that of pure Ni0.85Se and MoSSe, respectively. In the degradation of tetracycline hydrochloride, it displayed the largest degradation rate, boosting it 2.81 and 10.3 times that of Ni0.85Se and MoSSe, respectively. In hydrogen evolution reaction and oxygen evolution reaction, the Ni0.85Se/MoSSe heterojunction photocatalyst had Tafel slope of 58 and 37 mV/dec, respectively, which were both much lower than Ni0.85Se (77 and 171 mV/dec) and MoSSe (102 and 389 mV/dec). With structure and morphology analysis, the MoSSe has a 3D reticular structure which is more suitable for loading 0D Ni0.85Se nanoparticles to construct a 0D/3D heterostructure, where carriers generated in Ni0.85Se will be easily collected by MoSSe to accelerate the carriers’ separation and transmission. Moreover, the conduction band and valance band of MoSSe are both lower than those of Ni0.85Se, forming a type-II heterojunction where photoinduced electrons and holes will be separated to different sites. Thus, oxidation and reduction reactions will occur in different locations to demonstrate outstanding catalytic performance.