Construction of Conjugated Organic Polymers for Efficient Photocatalytic Hydrogen Peroxide Generation with Adequate Utilization of Water Oxidation.

The visible-light-driven photocatalytic production of hydrogen peroxide (HO) is currently an emerging approach for transforming solar energy into chemical energy. In general, the photocatalytic process for producing HO includes two pathways: the water oxidation reaction (WOR) and the oxygen reduction reaction (ORR). However, the utilization efficiency of ORR surpasses that of WOR, leading to a discrepancy with the low oxygen levels in natural water and thereby impeding their practical application. Herein, we report a novel donor-bridge-acceptor (D-B-A) organic polymer conjugated by the Sonogashira-Hagihara coupling reaction with tetraphenylethene (TPE) units as the electron donors, acetylene (A) as the connectors and pyrene (P) moieties as the electron acceptors. Notably, the resulting TPE-A-P exhibits a remarkable solar-to-chemical conversion of 1.65% and a high BET-specific surface area (1132 m·g). Furthermore, even under anaerobic conditions, it demonstrates an impressive HO photosynthetic efficiency of 1770 μmol g h, exceeding the vast majority of previously reported photosynthetic systems of HO. The outstanding performance is attributed to the effective separation of electrons and holes, along with the presence of sufficient reaction sites facilitated by the incorporation of alkynyl electronic bridges. This protocol presents a successful method for generating HO via a water oxidation reaction, signifying a significant advancement towards practical applications in the natural environment.