Hydrothermal preparation of nanoblock-like C doped WO3 for enhanced photocatalytic degradation and electricity generation

Abstract

Anode materials are crucial for the performance of photocatalytic fuel cells. In this paper, C/WO₃ (CW) composite photoanodes with different mass fractions were prepared by modifying WO₃ with non-metallic carbon (C) using a hydrothermal method and characterized by using analytical methods such as XRD, SEM, XPS, PL, UV–Vis DRS and EIS. The micro-morphological and structural characterization showed that the composites were successfully prepared. The incorporation of C expanded the light absorption range of the samples towards the visible light, and the lower energy required for the electron leaps guided the ordered movement of electrons and ions more efficiently. Analysing the PFC mechanism, it was found that C has a good electron storage capacity making it act as an electron acceptor to capture the off-domain electrons and provides more reactive radicals to enhance the light trapping ability of the complex. The degradation test results showed that 10 % wt (10-CW) was the optimal complex ratio, and the degradation rate of RhB reached 87.8 %. The study demonstrated that utilizing the C/WO₃ photoanode for shale gas flowback wastewater remediation achieved optimal performance within a 4-h treatment period. Experimental results showed the 10-CW anode PFC attained 70 % chemical oxygen demand (COD) reduction while exhibiting notable electrical characteristics: 245.5 mV open-circuit potential (V_oc), 400 mA/m² short-circuit current density (J_sc), and 9.0 mW/m² maximum output power density (P_max). These findings indicate that the fabricated C/WO₃ composite possesses significant potential as an efficient photoactive material for industrial wastewater purification applications.