Efficient tetracycline degradation and electricity production in photocatalytic fuel cell based on ZnO nanorod/BiOBr/UiO-66-NH2 photoanode and Cu2O/CuO photocathode

Photocatalytic fuel cells (PFC) provide a new approach to organic pollutants degradation from wastewater and energy generation. A new type of dual photocatalytic fuel cell (PFC) consisted of a ZnO NRs/BiOBr/UiO-66-NH2 (ZBU) photoanode and a Cu2O/CuO/Cu photocathode was constructed for tetracycline (TC) degradation, and simultaneously electricity production. The photodegradation and electrochemical properties gained at the ZBU/FTO photoanode are better than those of ZB/FTO and ZnO/FTO. The synthesized electrodes were characterized by XRD, FE-SEM, EDX, TEM, UV–Vis DRS, and PL analyses. The tests performed in the PFC system displayed that the closed-circuit removal efficiency is better than that in the open-circuit. At optimum conditions: light intensity = 10.13 mW/cm2, time = 45min, pH = 6.8, and TC concentration = 20 mg/L, the efficiency of TC degradation and the maximum output power were obtained at 97.1%, and 29.26 μW/cm2, respectively. The effects of the NaCl, NaHCO3, and Na2SO4 electrolytes were evaluated, and the current density of the Na2SO4 electrolyte was about 1.8 and 1.5 times higher than those of the NaHCO3 and NaCl electrolytes, respectively. The new PFC system showed well reusability after four cycles. [Display omitted] •A ZnO nanorods/BiOBr/UiO-66-NH2 photoanode was fabricated.•CuO/Cu2O photocathode via single-stage synthesis was formed on the Cu mesh.•The PFC exhibited high performance in Tetracycline degradation (45min/97.1%) and electricity generation (26.25 (μW/cm2)).•The PFC presented high reusability during 4 cycling degradation experiments.