Fabricating S‐Scheme Heterojunction via D‐A Type COF and ZnIn 2 S 4 Quantum Dots: An Efficient Strategy for Photocatalytic Generation of Hydrogen Peroxide

ABSTRACT In this study, a donor‐acceptor (D‐A) conjugated design strategy was used to synthesize a novel covalent organic framework (NLCOF, the COF initiated by Na Lv), using 2,5‐dimethoxylterephthalaldehyde as the building block via the Kröhnke reaction. Subsequently, ZnIn 2 S 4 quantum dots (ZIS QDs) were physically combined with NLCOF for constructing a ZIS QDs‐NLCOF S‐scheme heterojunction composite photocatalytic system. This system achieved an H 2 O 2 production rate of 6 417 µmol·g −1 ·h −1 in pure water using the 40ZIS‐NLC composite catalyst, which was 4.2 and 26.7 times higher than that of ZIS QDs and NLCOF, respectively. Upon adding 1 mL benzyl alcohol to the system, the H 2 O 2 production rate drastically increased to 53 383 µmol·g −1 ·within 5 h. Advanced characterization techniques, including XPS, KPFM, and EPR were employed to elucidate the intrinsic mechanism of S‐scheme heterojunction photocatalytic H 2 O 2 production. This study offers insights into the rational design of high‐performance COF‐based heterojunction photocatalysts and provides a robust foundation for optimizing interfacial electron‐coupling interactions to enhance overall photocatalytic efficiency.