Application of Redox Mediators in Bioelectrochemical System

Abstract

Bioelectrochemical systems (BESs), using solid-state electrodes as either electron acceptors or electron donors to drive microbial reactions, have attracted increasing attention in the past decade for the bioremediation. The treatability of various pollutants by BESs has been proved in lab scale. However, these technologies are still far from the real application. One of the greatest challenges is the difficulty of achieving high rates of extracellular electron transfer (EET) between microorganisms and electrode. To overcome this barrier, redox mediators (RMs) were applied to the BESs for enhancing the EET. Herein, we provide an overview of artificially synthetic or natural presented RMs that reported so far, particularly discussing and highlighting in brief the natural-presented, solid-phase humin, as RMs for enhancing the biotransformation of contaminants in BESs. Conclusions have been drawn from the literature reviewed, and suggestions for future research on enhancing the applicability of BESs assisted by redox mediators were proposed.