Control of bacterial extracellular electron transfer by a solid-state mediator of polyaniline nanowire arrays

We report that polyaniline nanowire arrays (PANI-NAs) can serve as a tunable terminal polymeric mediator for bacterial extracellular electron transfer (EET) by members of the genus Shewanella. Multiple oxidation levels of PANI at different applied potentials lead to multiple abilities in mediating EET, while the aligned nanostructures enable enhanced local topological interactions with microbes and hence efficient electrical interaction. PANI-NA therefore exhibits a unique property that allows for efficient EET reactions to proceed in a controlled manner.