Construction of Highly Dispersed Ni Sites on N‐rich Carbon Nitride for Enhanced Photocatalytic NO Removal

Abstract Intelligent active site engineering to harness photogenerated charge carriers and motivate surface reactions is at the core of catalysis. Herein, highly dispersed Ni sites are planted on C 3 N 5 , an N‐rich carbon nitride, by a facial two‐step annealing method to construct a Ni‐C 3 N 5 material. The incorporation of Ni sites can significantly enhance the e – /h + separation efficiency of C 3 N 5 under light irradiation and promote the activation of O 2 to produce reactive oxygen species. Compared with pristine C 3 N 5 (with NO removal ratio of ≈35%), the as‐prepared 0.1‐ or 0.25‐Ni‐C 3 N 5 material can remove ≈54% continuous‐flowing NO (initial concentration: 600 ppb) quickly in less than 25 min under white LED light irradiation. The long‐term photocatalytic performance demonstrates that the catalyst is stable without obvious attenuation in activity. The findings of the trapping experiments and in situ diffuse reflectance infrared fourier transform spectroscopy tests suggest that • O 2 − may mainly convert NO into NO 2 , while • OH and 1 O 2 play a significant role in the NO 2 to NO 3 – conversion reaction. The present work brings new insights into the design of active sites on semiconductor photocatalytic materials for the treatment of NO x species.