Abiotic-biotic hybrid for CO2 biomethanation: From electrochemical to photochemical process.

Fang, Zhen; Zhou, Jun; Zhou, Xiangtong; Koffas, Mattheos A G

Converting CO2 into sustainable fuels (e.g., CH4) has great significance to solve carbon emission and energy crisis. Generally, CO2 methanation needs abundant of energy input to overcome the eight-electron-transfer barrier. Abiotic-biotic hybrid system represents one of the cutting-edge technologies that use renewable electric/solar energy to realize eight-electron-transfer CO2 biomethanation. However, the incompatible abiotic-biotic hybrid can result in low efficiency of electron transfer and CO2 biomethanation. Herein, we present the comprehensive review to highlight how to design abiotic-biotic hybrid for electric/solar-driven CO2 biomethanation. We primarily introduce the CO2 biomethanation mechanism, and further summarize state-of-the-art electrochemical and photochemical CO2 biomethanation in hybrid systems. We also propose excellent synthetic biology strategies, which are useful to design tunable methanogenic microorganisms or enzymes when cooperating with electrode/semiconductor in hybrid systems. This review provides theoretical guidance of abiotic-biotic hybrid and also shows the bright future of sustainable fuel production in the form of CO2 biomethanation.