High‐concentration single‐atom Zn‐doped porous tubular g‐C ₃ N ₄ : a superior photocatalyst for tetracycline hydrochloride degradation and bacterial sterilization

Abstract High‐concentration single‐atom doping remains a formidable challenge due to the propensity for single atoms to form clusters or aggregate at elevated concentrations. Herein, high‐concentration (10.8 wt%) Zn single‐atom‐doped porous tubular g‐C 3 N 4 (ZCN) was successfully obtained via a template‐free, one‐step calcination method, exhibiting excellent photocatalytic performance. The confinement of the pore walls suppresses the Zn atom’s migration and aggregation, enhancing the Zn single‐atom stability. ZCN exhibited excellent photodegradation performance against tetracycline with outstanding stability. Moreover, ZCN displayed remarkable sterilization performance, achieving a 100% inactivation of Staphylococcus aureus within 90 min of visible‐light exposure. Density functional theory calculations demonstrated that the Zn single‐atom sites act as pivotal photocatalytic active sites, with the presence of Zn single atoms notably augmenting charge separation efficiency. This work provides a novel approach for managing photocatalytic efficiency through enlarging single‐atom doping, offering an avenue for pollutant photodegradation and sterilization.