High‐performance Cu₂O‐based photocatalysts enabled by self‐curling nanocelluloses via a freeze‐drying route

Abstract Enhancing the photocatalytic stability of Cu 2 O in the degradation of tetracycline is a great challenge in combating environmental water pollution because it is prone to deactivation by photocorrosion in aqueous environment. In this study, Cu 2 O/cellulose microfiber aerogel is synthesized through freeze‐drying, utilizing the self‐curling effect of cellulose and then calcined to produce Cu 2 O/C composite aerogel. The derived Cu 2 O/C composite aerogel features hollow carbon microfibers anchored with Cu 2 O nanocubes. Due to the curling structure and conductivity of the carbon microfibers, the photodegradation efficiency of the obtained Cu 2 O/C composite aerogel for tetracycline is drastically improved to 97.3% under 120 min of visible‐light irradiation, and remains a cycling photodegradation rate of 84.3% after 10 cycles. The Cu 2 O/C composite aerogel shows remarkable strategies for designing and constructing Cu 2 O‐based photocatalyst in the practical photodegradation of tetracycline under visible‐light exposure.