Transitional bimetallic heterostructure catalyst modified anode for microbial fuel cell treatment of high-intensity wastewater

Abstract

In this paper, transitional bimetallic catalysts (FeS2/MoS2) were prepared by a simple one-step hydrothermal method, which were directly applied to MFC anodes for the treatment of high-concentration wastewater with simultaneous biopower generation. The obtained catalysts were highly biocompatible and favorable for inducing the enrichment of electroactive microorganisms and shortening the initiation cycle. The maximum power density (Pmax) and current density of the obtained anode reached 2.87 W·m−2 and 4.37 A·m−2 under 4000 mg·L−1 influent, which were 171% and 65% higher than that of bare carbon cloth, respectively. The chemical oxygen demand (COD) removal rate reached 98.82%. 16 S rRNA gene sequence analysis showed that the main electrophilic microorganisms induced by FeS2/8%MoS2-modified anodes were Synergistota (30.94%) and Geoalkallbacter (15.93%) compared to CC anodes. The resulting anode possesses excellent redox activity and high biocompatibility, and is simple and inexpensive to prepare. More importantly, it accelerated the extracellular electron transfer rate at the interface between the electroactive bacteria and the anode, providing a new idea of choice for single-chamber microbial fuel cells for low-cost treatment of high-concentration wastewater.