Boosting piezo-photocatalytic performance in antibiotic wastewater treatment through graphitic carbon nitride–zinc oxide based heterojunction engineering

Abstract

Semiconductor photocatalytic technology is confronted with the key challenge of rapid recombination of photogenerated carriers. This work successfully fabricates a flexible g-C₃N₄–ZnO@PVDF composite film via a facile phase inversion method. Its principal innovation lies in the effective coupling of the material's inherent photovoltaic properties with the piezoelectric effect derived from PVDF under mild mechanical agitation (aeration). This synergy establishes a powerful built-in electric field that dramatically enhances the separation and migration of photogenerated charge carriers. The film exhibits superior performance in the degradation of the antibiotic Tetracycline (TC, 20 mg L⁻¹), achieving over 99% removal under optimal conditions. The built-in piezoelectric field not only boosts photocatalytic efficiency but also enables a self-powered purification capability. The system demonstrates excellent stability and reusability, presenting a promising and sustainable strategy for advanced wastewater treatment.