Design of Optimized PEDOT‐Based Electrodes for Enhancing Performance of Living Photovoltaics Based on Phototropic Bacteria

Abstract

Living photovoltaics represent a growing class of microbial devices that are based on whole cell–electrode interactions. The limited charge transfer at the cell–electrode interface represents a significant bottleneck in realizing an efficient technology. This study focuses on the development of poly(3,4‐ethylenedioxythiophene) (PEDOT)‐based electrodes that are electrosynthesized in the presence of a sodium dodecyl sulphate (SDS) dopant. Potentiodynamic and potentiostatic electrochemical techniques, as well as scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy, and theoretical modelling of the electropolymerization transient, are employed to create and characterize PEDOT electrodes under various conditions. The electrodes are able to capture photosynthetically derived current under multiple light–dark cycles when interfaced with Synechocystis sp. PCC 6803. In the presence of the Synechocystis, the PEDOT electrodes show a sixfold and twofold enhancement over conventional graphite electrodes for both mediatorless and K3Fe(CN)6‐mediated conditions, respectively. The ability of these electrodes to enhance extracted photocurrent for both direct and indirect electron transfer mechanisms provides a versatile platform for improving various microbial devices.

Arraying of microphotosynthetic power cells for enhanced power output

“…Accordingly, this ability to self-replicate the cellular components in cyanobacteria enhances the longevity of algal cells 6 , 24 , 27 , thereby increasing the longevity of the microphotosynthetic power cell performance. Therefore, µPSCs containing whole living photosynthetic organisms outperform µPSCs that are based on cellular pigments, with extended stability, better performance, and lower maintenance costs 1 , 28 , 29 . In addition to these advantages, designing µPSCs with better flow regimes would enable the photosynthetic microorganisms to undergo self-repair and generate power continuously.…”

Electrogenic Bacteria Promise New Opportunities for Powering, Sensing, and Synthesizing

“…PCC6803 in the electropolymerized PEDOT electrode. [ 188 ] Jiang and co‐workers created a living electrode by converting graphene oxide (GO) to conductive reduced GO with G. sulfurreducens . [ 189 ] The bacterial EET process directly reduced GO, developing a seamless integration of the living bacteria and abiotic electrode.…”

Gold Nanoparticle Interaction in Algae Enhancing Quantum Efficiency and Power Generation in Microphotosynthetic Power Cells

“…offers much promise in enriching photosynthetic microbes to produce electron mediators for an improved indirect electron transfer process. [19,20] Another possible method to enhance electron transfer is utilizing external electron mediators such as methylene blue, potassium ferricyanide, etc., which siphon through the electron transport chains of the photosynthetic cells and mediate the electrons to the electrode surfaces. That inevitably increases performance by %30%.…”

“…[31] The μPSC with whole living photosynthetic organism allows for continuous repair of proteins damaged by high-energy photons, [6,15,31] and these μPSCs outperform μPSCs which are based on cellular fragments in terms of extended stability, better performance, and lower maintenance costs. [3,19,53] Despite several advantageous offered by μPSCs, real-time applications are limited by low stability and efficiency issues. [17] Such limitations can be overwhelmed with augmented capabilities enabled by NPs.…”