Amplified treatment of mariculture effluent and pathogen with synchronously electricity generation in a self-biased photocatalytic fuel cell based on dual photoelectrode

Abstract

A device capable of producing electricity from wastewater treatment process is highly desirable as it addresses critical challenges in sustainable energy generation and environmental conservation. In this work, a highly efficient three-dimensional (3D) porous network structured In₂O₃/ZnO/FTO photoanode and a flower-like Cu₂O/CuO/Cu cathode were successfully fabricated and integrated into a visible light-driven photocatalytic fuel cell (PFC) system. Material characterization revealed that In₂O₃ was well-dispersed on the 3D porous ZnO network, proving ample active sites for photoelectrocatalysis. The PFC utilizing mariculture effluent containing chlortetracycline hydrochloride (CTCH) as a fuel source, achieved an open-circuit voltage of 559 mV and a maximum power density of 0.3084 μW cm⁻² under visible light irradiation. Furthermore, the system demonstrated a CTCH removal efficiency of 91.5 %, outperforming ZnO/FTO and In₂O₃/FTO electrodes in terms of degradation efficacy and energy conversion. Additionally, the cell demonstrated outstanding recyclability and remarkable antimicrobial efficacy against Escherichia coli and Bacillus cereus, underscoring its superior functionality. The boosted photoelectrocatalytic activity was credited to the formation of the In₂O₃/ZnO/FTO heterojunction within the porous network-structure, which provided a high specific surface area and favorable optical and electronic traits and thereby, improving the overall efficiency of the dual photoelectrode system. This PFC device facilitates simultaneous electricity generation, pollutant degradation and bacterial sterilization, offering promising multifunction applications.