Decoration of Cu2O-T with controllable crystal planes on nitrogen vacancies-engineered graphitic carbon nitride nanosheets: Coupling in situ generation and activation of H2O2 in a photo-Fenton-like system

The photo-Fenton method presents a promising approach for wastewater treatment, yet it faces several significant challenges, including the continuous supply of H 2 O 2 , slow mass transfer rates and a limited operational pH range. In this context, we describe the successful preparation of a novel catalyst: n-p type graphitic carbon nitride nanosheets engineered with nitrogen vacancies and decorated with Cu 2 O-T, which is characterized by controllable crystal planes. This photo-self-Fenton-like catalyst is designed for the in-situ production and activation of H 2 O 2 . The optimized catalyst, CNC-20, demonstrates remarkable efficiency in degrading various organic pollutants, showcasing high cyclic stability and wide applicability. Notably, CNC-20 achieves a degradation rate of 98.8% for tetracycline hydrochloride within 60 min, with a reaction rate constant 4.2 times greater than that of pristine carbon nitride. Characterization studies illustrate that the construction of ultrathin carbon nitride nanosheets featuring nitrogen vacancies, combined with the co-exposure of Cu 2 O-T crystalline planes (111) and (100), significantly enhances carrier separation efficiency, thereby facilitating effective H 2 O 2 generation. Furthermore, Cu 2 O-T plays a crucial role in the direct capture of in-situ generated H 2 O 2 , rapidly activating it to generate abundant ·OH, which effectively mitigates the issue of slow mass transfer associated with H 2 O 2 . This study presents a novel approach integrating in-situ H 2 O 2 generation and activation, effectively overcoming the inherent limitations of traditional photo-Fenton reactions and providing a promising strategy for pollutant degradation in wastewater treatment systems.