Nickel phosphide modified nickel cobaltate as microbial fuel cell anode to facilitate the treatment of shale gas flowback wastewater: Electricity generation performance and mechanism

Abstract

How to treat the actual shale gas flowback wastewater (FW) is a serious challenge for the unconventional gas industry. Herein, an environmentally friendly and energy reusable green technology microbial fuel cell（MFC）is reported. Ni-P is electrodeposited on NiCo₂O₄/ carbon cloth (CC) electrode as the anode of MFC and used to treat actual FW to observe the power generation and degradation performance. The high conductivity and large specific surface of the composites positively improve the formation of biofilm on the electrode surface and reduce the influence of electron transfer. Moreover, the smaller charge transfer resistance of the composite electrode compared to the CC and NiCo₂O₄/CC lays the foundation for its excellent power production performance. As the Ni-P@NiCo₂O₄ anode MFC is run for 34 days, there is a maximum output voltage of 522.4 mV, and the removal of chemical demand is 61.55 %, which is better than the CC (26 d, 362.5 mV, 49.74 %). High-throughput testing shows that Desulfobacterota is the dominant electroactive bacterium and that modified electrodes can dramatically alter the enrichment of the dominant species. Therefore, this work is important for the resource utilization of FW, practical application and performance improvement of MFC.