Efficient rifampicin degradation and simultaneous energy recovery in photocatalytic fuel cell based on the enhanced PMS and H2O2 synergistic activation on sulfur-doped CuMnO/carbon felt cathode

Abstract

Photocatalytic fuel cells (PFC) as a potential green technology has been widely reported. In this study, a PFC/peroxymonosulfate (PMS) system with sulfur-doped CuMnO/carbon felt as the cathode to promote the co-activation of PMS and H2O2 was constructed for efficient rifampicin (RIF) wastewater purification and synchronous power generation. The experimental results demonstrate that sulfur introduction makes the specific surface area of CuMnO increase and the stability of the system improve. Compared with the PFC system alone, PFC/PMS system exhibited excellent RIF degradation performance in 15 min with a removal ratio of 96.9 % and a TOC removal ratio of 78.12 %. Free radical quenching experiment and EPR test results give certification of the fact that •OH, 1O2, O2•−, and SO4·- played a crucial part in RIF degradation. Furthermore, the constructed system demonstrated stable electricity generation performance during the degradation process with a short-circuit current density of 0.57 mA cm−2, open-circuit voltage of 2.75 V, and maximum power output of 0.78 mW cm−2. This work provides a sustainable approach for organic wastewater purification with high mineralization ratio.