D-A COFs/ZnIn2S4 for high-efficiency H2O2 photosynthesis

The construction of dual built-in electric field (IEF)-driven S-scheme heterojunctions presents a promising strategy to accelerate efficient charge separation and improve charge utilization in photocatalytic H₂O₂ production. Herein, we report, the construction of a heterojunction based on donor-acceptor covalent organic frameworks (D-A COFs) TpAQ and ZnIn₂S₄ (ZIS), realizing a dual IEF-driven S-scheme heterojunction—one from the heterojunction interface and another from D-A interface within D-A COFs. In particular, the optimized TpAQ/ZIS-10 exhibits a significantly higher visible-light driven photocatalytic H₂O₂ production rate of 2362 μmol g⁻¹ h⁻¹ in pure water than TpAQ and ZIS by utilizing both the oxygen reduction reaction and water oxidation reaction pathways. Furthermore, the experimental results and theoretical calculations revealed that the synergistic effect of dual IEF in TpAQ/ZIS heterojunction significantly facilitates efficient charge carrier transfer and separation. This work provides valuable insight for constructing highly efficient S-scheme heterojunctions with dual IEF.

This work entitled “Dual built-in electric field-driven S-scheme heterojunction of D-A COFs/ZnIn₂S₄ for accelerated charge separation toward high-efficiency H₂O₂ photosynthesis in pure water” was published on Acta Physico-Chimica Sinica (published on September 1, 2025).