Dopamine-perylene diimide polymer with a donor–acceptor structure enhance interfacial electric field for improved H2O2 photosynthesis

Photocatalytic synthesis of hydrogen peroxide (H 2 O 2 ) from H 2 O and O 2 is economically attractive, but its sluggish kinetics are challenging due to ineffective electron–hole separation. A novel photocatalyst for scalable H 2 O 2 production (SA-PDI@PDA) was constructed from self-assembled perylene diimide (SA-PDI) modified with dopamine (PDA) via electrostatic interaction. The donor–acceptor interface generates a 1.6-fold stronger interfacial electric field that enhances charge separation and enables the extraction of highly reductive electrons that increase the H 2 O 2 production rate 5.4-fold. The phenolic groups in PDA act as proton pockets, providing additional protons that accelerate H 2 O 2 production to 4873 μmol g⁻¹ h⁻¹ , with an apparent quantum yield of 12.35 % at 420 nm. This study provides valuable insight into the design of photocatalysts for enhanced and sustainable H 2 O 2 generation that is suitable for in situ sterilization and organic pollutant degradation applications.