Performance and mechanism of biobased-supported conjugated polymer donor with dual small-molecule acceptors

Abstract

Sodium pentachlorophenate (PCP-Na) is a persistent and toxic chlorinated pollutant frequently detected in industrial wastewater. Herein, a fully organic photocatalytic system was developed by integrating coconut shell carbon with organic photovoltaic active-layer materials. A ternary donor-acceptor-acceptor heterojunction (PM6:Y6:IEICO-4F) was constructed to enhance visible-light harvesting and interfacial charge separation. The cascaded energy-level alignment and type-II heterojunction structure broaden light absorption (500-900 nm), suppress carrier recombination, and facilitate charge transfer. Under 300 W xenon lamp irradiation, the optimal photocatalyst achieved 99% degradation of 50 mg/L PCP-Na, within 40 min, and exhibited excellent cycling stability. Superoxide radicals (·O₂^-) and photogenerated holes (h⁺) are identified as the dominant reactive species, driving stepwise dechlorination and ring-opening processes. This work reveals that the biochar-supported ternary D-A/A type-II heterojunction enables exceptional visible-light utilization and efficient carrier separation, offering a novel all-organic platform for remediating persistent chlorinated pollutants.

Keywords

Non-fullerene / organic photocatalyst / photodegradation / sodium pentachlorophenate

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