NixP and Mn3O4 dual co-catalysts separately deposited on a g-C3N4/red phosphorus hybrid photocatalyst for an efficient hydrogen evolution

Abstract

Recently, much attention has been focused on the development of photocatalysts for hydrogen evolution. Up to now, efficient hydrogen generation is still greatly challenging due to the restraints of the surface redox reaction rate, and the introduction of a co-catalyst is one of the keys to this problem. Here, dual non-noble co-catalysts Ni_xP and Mn₃O₄ were proposed and prepared on a g-C₃N₄/red phosphorus (CNP) hybrid structure with a high light adsorption capability by a two-step photo-deposition method. The photo-excited charge on the composite catalyst separate and transfer from C₃N₄ to red phosphorous due to a type I heterojunction structure. Ni_xP and Mn₃O₄ act as reductive and oxidative co-catalysts, respectively. The hydrogen production rate was 5851.3 μmol g⁻¹ h⁻¹, 12.4 times that of pure CNP. The consistent catalytic activity in an actual 25 mL flask for hydrogen evolution over eight hours accumulated 245.08 μmol H₂ under solar simulated irradiation. This work provides practical reference for the development of a novel inexpensive photocatalyst system.