Graphene-based materials for electrochemical CO2 reduction

Electrocatalytic CO2 reduction (ECR) using renewable electricity provides an alternative strategy for alleviating energy shortage and global warming issues. To facilitate this kinetically sluggish process, the design of highly selective, energy-efficient, and cost-effective electrocatalysts is key. Graphene-based materials have features of relatively low cost, excellent electrical conductivity, tunability in structure and surface chemistry, and renewability, rendering them competitive for CO2 electroreduction. In particular, by doping with heteroatoms, it's possible to create unique active sites on graphene for CO2 adsorption and activation. Besides, integration of graphene with other materials enables creation of a synergistic effect, thereby boosting CO2 conversion. This review focuses on recent advances of graphene-based catalysts in ECR. The relationship between structure and property with regard to CO2 electroreduction is highlighted. Leading electrocatalysts are discussed and compared with some metal benchmark materials to provide an evolutionary perspective of performance progress. Development opportunities and challenges in the field are also summarized.