Bioelectrochemical conversion of CO2 to valuable chemicals through microbial electrosynthesis: State-of-the-art for current progress on green strategies with circular economy nexus

Abstract

The rising global concerns over climate change and the urgent need for sustainable energy have accelerated research into cutting-edge technologies for converting CO₂ to valuable compounds. One promising approach involves microbial electrosynthesis (MES) for converting CO₂ into biofuels and platform chemicals, utilising electrotrophic microorganisms as biocatalysts. Nevertheless, low productivity of value-added chemicals and non-optimised MES configurations, including substrate limitation, are noteworthy bottlenecks that hinder the scalability of this technology. To overcome these limitations, researchers have explored different reactor designs and electrode modifications with biotic and abiotic catalysts to improve the interaction between materials and microbes, ultimately leading to increased product yield. Hence, this review emphasises the insights of MES in the context of reactor configurations and the modification of electrode material via nature-based strategy with life cycle assessments for driving a circular carbon economy. Besides, different genetic and synthetic biological processes, integration of quorum sensing, 3D printing, and machine learning as novel and promising approaches, along with challenges and future perspectives to advance MES, are highlighted in the present review, which has not been critically reviewed to date. Thus, this review attempts to present a holistic assessment of the applicability of MES that intends to guide researchers in assessing the feasibility of this technology by integrating inexpensive and non-energy-intensive green strategies.