Powering the World with Solar Fuels from Photoelectrochemical CO2 Reduction: Basic Principles and Recent Advances

Abstract Carbon neutrality has become an urgent mission for the future of mankind. Powering the world with renewable energy from solar CO 2 reduction represents a promising way to accomplish this target. Photoelectrochemical (PEC) CO 2 reduction, integrating the merits of photocatalysis and electrocatalysis, offers an intriguing and effective approach to realizing solar fuel production and CO 2 mitigation in one shot. To stimulate research efforts in PEC CO 2 reduction, a comprehensive review of recent advances in this field is presented, with a special emphasis on the general design motives for the assembly of highly efficient PEC cells. First, basic principles and evaluating parameters of PEC CO 2 reduction cells are introduced. Then, recent innovative PEC cells with highly active photocathodes for CO 2 reduction to different target chemicals are highlighted and the material designing principles are discussed. In addition, the representative self‐biased PEC CO 2 reduction cells including the tandem and artificial‐leaf configurations are also addressed. Finally, this review is concluded with remarks on the present achievements in PEC CO 2 reduction to different chemicals, pointing out some effective strategies to promote the efficiencies for solar fuel production. A vision of the challenges and opportunities for how to forward PEC CO 2 reduction research is further provided.