D-A type porous organic polymers with NDI/PDI units for efficient photocatalytic H2O2 production

This work reports the construction of two three–component conjugated porous polymers, denoted as NDI-POP and PDI-POP. These polymers incorporate naphthalene diimide (NDI) or perylene diimide (PDI) as acceptor units, with 2–hydroxy–1,3,5–benzenetetracarboxaldehyde (TP) and 2,4,6–trihydroxy–1,3,5–benzenetetracarboxaldehyde (DHTA) serving as donor units. By precisely regulating the donor–acceptor (D-A) synergistic interactions within the conjugated framework, the as–synthesized POPs exhibited a narrower bandgap, strong photocurrent response, and low impedance. Under visible light irradiation and an oxygen (O 2 ) atmosphere, NDI-POP achieves a hydrogen peroxide (H 2 O 2 ) production rate of 2000 μmol g –1 h –1 in pure water without the involvement of sacrificial reagents, which was 3.39 times of that achieved with the PDI-POP photocatalyst. Photocatalytic cycling experiments further confirm excellent recyclability for both materials. Additionally, controlled experiments verify that efficient H 2 O 2 production proceeds via 2e⁻ oxygen reduction reaction (ORR) pathway. This study provides valuable insights into the regulation of d -A type porous organic materials for enhanced H 2 O 2 generation.