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