Ultrafast synthesis of near-zero-cost S-doped Ni(OH) 2 on C 3 N 5 under ambient conditions with enhanced photocatalytic activity.

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 C 3 N 5 as a model semiconductor, an impressive near-zero-cost 2D S-doped nickel hydroxide (S-Ni(OH) 2 ) is grown on C 3 N 5 ultrafast within 30 min under ambient conditions by facile reaction between extremely low-cost Ni(NO 3 ) 2 and Na 2 S in aqueous solution. The fabricated 2D S-Ni(OH) 2 -C 3 N 5 hybrid exhibits enhanced photocatalytic performance for both H 2 production from water and NO removal for air purification. The H 2 production rate on S-Ni(OH) 2 -C 3 N 5 is ∼7 times higher than that of Ni(OH) 2 -C 3 N 5 and even slightly higher than that of Pt-C 3 N 5 , 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 H 2 production is reached on 1.0 wt% S-Ni(OH) 2 -C 3 N 5 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.