Degradation of refractory organic compounds by photocatalytic fuel cell with solar responsive WO3/FTO photoanode and air-breathing cathode

A novel solar responsive photocatalytic fuel cell (PFC) consisted of a WO3/FTO photoanode and an air breathing cathode was successfully prepared for simultaneous pollutant degradation and power production. The as-prepared PFC system exhibited outstanding photocurrent performances, which were attributed to the combined effects of the large specific surface area and the improved oxygen transportation by air-breathing cathode design, as well as the enhanced light absorption by transparent FTO substrate. Oxytetracycline hydrochloride was used as the model compound in this paper, and parametric effects on the PFC performances were deeply investigated. Results showed that increasing electrolyte concentration and light density were effective approaches to enhance power outputs. In terms of oxytetracycline hydrochloride concentration, the maximum power density firstly enhanced when oxytetracycline hydrochloride concentration increased to 0.5 mmol/L, then dropped dramatically with further increasing of oxytetracycline hydrochloride concentration to 2.0 mmol/L. The highest short-circuit current density of 372.4 mu A/cm(2) and maximum power density of 36.3 mu W/cm(2) were obtained when the PFC operated at the optimum operation condition of 0.1 mol/l Na2SO4 electrolyte, 200 mW/cm(2) light density and 0.5 mmol/L oxytetracycline hydrochloride. The PFC-assisted photocatalytic degradation experiments also suggested a promising application of the as-prepared PFC system in refractory wastewater treatment. (C) 2017 Elsevier Inc. All rights reserved.