Ultrafast synthesis of near-zero-cost S-doped Ni(OH)2 on C3N5 under ambient conditions with enhanced photocatalytic activity

Abstract

Planting highly efficient and low-cost Ni-based noble-metal-free active sites on semiconductors is of great significance in the field of photocatalysis. Herein, taking wide visible-light-responsive 2D C₃N₅ as a model semiconductor, an impressive near-zero-cost 2D S-doped nickel hydroxide (S–Ni(OH)₂) is grown on C₃N₅ ultrafast within 30 min under ambient conditions by facile reaction between extremely low-cost Ni(NO₃)₂ and Na₂S in aqueous solution. The fabricated 2D S–Ni(OH)₂–C₃N₅ hybrid exhibits enhanced photocatalytic performance for both H₂ production from water and NO removal for air purification. The H₂ production rate on S–Ni(OH)₂–C₃N₅ is ∼7 times higher than that of Ni(OH)₂–C₃N₅ and even slightly higher than that of Pt–C₃N₅, demonstrating its potential as a candidate for noble metal catalysts like Pt. In particular, an apparent quantum yield (AQY) value of 30.9% at 420 nm for H₂ production is reached on 1.0 wt% S–Ni(OH)₂–C₃N₅ due to quick internal charge transfer efficiency. In addition, ∼42% of NO can be purified in a continuous flow reaction system. This work affords a cost-efficient strategy to steer the photocatalytic property of Ni-based catalysts.