Ultrathin Ni(OH)2 nanosheets: a new strategy for cocatalyst design on CdS surfaces for photocatalytic hydrogen generation

Abstract

Ultrathin metal materials exhibit quantum size and surface effects that give rise to unique catalytic properties. In this paper, we report a facile liquid synthesis method for polyvinylpyrrolidone (PVP, K30) capped ultrathin Ni(OH)₂ nanosheets with lamellar structure. The as-prepared ultrathin Ni(OH)₂ nanosheets coupled with CdS nanorods exhibit excellent activity in hydrogen generation from water splitting under visible light. The H₂ evolution rate of Ni(OH)₂/CdS, 40.18 mmol h⁻¹ g_Cat.⁻¹ with a quantum efficiency of 66.1% at 420 nm, is ca. 1.5 times that of Pt/CdS with an optimal loading amount (1.25 wt%) under the same reaction conditions. Considering the cost of photocatalysts, the ultrathin Ni(OH)₂ nanosheet coupled CdS photocatalyst may have a promising commercial application in photocatalytic hydrogen production.