Membraneless Photocatalytic Fuel Cell with Double Photoelectrodes for Simultaneous Electricity Generation and Pollutant Degradation

Abstract

Environmental pollution and new energy development have become topics of increasing concern. Herein, a visible-light-driven photocatalytic fuel cell (PFC) with double photoelectrodes was constructed for simultaneous electricity generation and pollutant degradation, in which graphitic carbon nitride (g-C3N4) generated on W/WO3 nanorod arrays (W/WNR/g-C3N4) was used as the photoanode and Fe3+-doped CuBi2O4 thin film on indium tin oxide (ITO) conductive glass (ITO/CBFeO) was used as the photocathode. The experimental results showed that the WO3/g-C3N4 Z-scheme structure and one-dimensional WNR rod-like structure could effectively suppress the recombination of photogenerated charge carriers and enable W/WNR/g-C3N4 to present a good photocurrent response under visible light irradiation. The Fermi level mismatch between the W/WNR/g-C3N4 photoanode and ITO/CBFeO photocathode could improve the transfer of photogenerated electrons from the photoanode to the photocathode across the external circuit, enabling the constructed PFC to afford high electricity output and good efficiency for pollutant degradation. The short-circuit current density and maximum power density could reach 620 μA cm−2 and 110 μW cm−2, respectively, while the degradation ratio of oxytetracycline reached 97.6% in 90 min. Therefore, the proposed PFC system provides a new way to generate electric energy and degrade pollutants simultaneously.