Peroxymonosulfate enhanced antibiotic removal and synchronous electricity generation in a photocatalytic fuel cell

Photocatalytic fuel cell (PFC) is promising owing to its synchronous organic pollutants removal and energy recycle, but it still remains to improve in the cell performance. Herein, we demonstrate a synergistic method adding peroxymonosulfate (PMS) into PFC to promote antibiotic tetracycline (TC) degradation and simultaneous electric power generation. The introduction of PMS could be activated by the photoelectric effects, also used as the electrolyte and electron acceptor, which could enhance the photoelectrocatalysis and spread the reaction space from the electrode surface to the whole system. Herein, the PFC/PMS augmented the TC decontamination by 82.83% and electricity production by 122.40% versus the PFC without introducing PMS, respectively. In addition, factors controlled namely PMS dosage, solution pH, and UV intensity were investigated for the cell performance of the coupling system. Furthermore, UV–Vis spectrum and TOC analysis confirmed the destruction mineralization of TC. Moreover, a series of radicals quenching experiments were implemented to explore the cooperative elimination mechanism, and the results indicated that hydroxyl and sulfate radicals played the key roles at the acidic condition, and the direct oxidation of PMS dominated the chief effect at the neutral environment, and singlet oxygen and superoxide anion acted the primary function in the alkaline circumstance.