Ariel Furst, Massachusetts Institute of Technology
Electrochemical systems that incorporate microbes are uniquely poised to meet challenges in renewable energy and sustainable chemical synthesis. By integrating electrochemical and whole-cell catalysis, these technologies simultaneously combine high energy efficiency with the ability to catalyze complicated multistep reactions. However, a major barrier to their use at scale is sluggish electron transfer between cells and electrodes, reducing overall efficiency.
By engineering a conductive polymer electrode, we boost the overall efficiency of microbe-electrode electron transfer. This enhancement is due to improved kinetics for mediator oxidation at the electrode. We further discover that these kinetic benefits result from an enzyme-like catalytic mechanism, in which an undesirable intermediate is thermodynamically destabilized to allow a higher efficiency reaction to dominate. Finally, we connect this catalytic property to the unique electrochemical structure of our polymer material. These results establish a new bio-inspired strategy for enhancing microbial electrocatalysis and establish material design principles for next generation electrode materials.
