An Overview of Solar-Driven Photoelectrochemical CO2 Conversion to Chemical Fuels

With accelerating consumption of nonrenewable energy resource, mankind is currently facing the dilemma of energy crisis and global warming caused by excessive greenhouse gas emissions. Photoelectrocatalytic (PEC) technique to convert the main greenhouse gas CO2 into hydrocarbon fuels can solve these two issues with one stone. Herein, we summarize the latest developments of semiconductor-based PEC CO2 reduction for solar fuels production in a more comprehensive manner. Our endeavors start with elucidation of the fundamental principles of CO2 reduction technology and influencing factors of PEC CO2 reduction technique, followed by specific introduction on four quintessentially designed PEC CO2 reduction systems, and then multifarious photoelectrodes utilized for these photosystems are systematically introduced. Modification rationales for crafting photoelectrodes with high conversion efficiency and good stability are elucidated. Besides, strategies developed for fine-tuning of selectivity of PEC CO2 reduction products are also discussed. Finally, future outlooks and challenges in this booming research field are reviewed. It is anticipated that our Review would provide enriched and guided information on rational construction of high-performance photoelectrodes for solar-to-chemical fuels conversion.