Anchoring Ag Atom on Carbon Vacancy Enriched Carbon Nitride to Synergistically Promote CO2 Photoredution with Water

Abstract Pristine carbon nitride (CN) has low CO 2 reduction ability due to its sluggish charge carriers transfer and CO 2 activation. Herein, carbon vacancy (CV) and Ag single atoms (SAs) with N2 coordination are simultaneously introduced into CN with the ordered structure for stable and efficient photoreduction of CO 2 in the presence of H 2 O. The optimal sample loaded with 0.053 wt.% Ag evolve 173.0 µmol g −1 CO in 3 h with 89% selectivity, which is 11.7 times higher than that of pristine CN (14.7 µmol g −1 ). Experiments and theoretical calculations reveal that the CV and Ag–N2 sites promote CO 2 adsorption/activation and the generation of * COOH and * CO. KSCN‐assisted calcination induces more ordered arrangement of melon chains, which can accelerate charge transfer/separation and facilitate H 2 O oxidation, thus accounting for the largely improved CO 2 photoreduction performance. This study adopts a new method to prepare Ag SA‐anchored and C‐deficient CN, and provides insights into their synergistic roles in enhancing CO 2 reduction.