Progress and Perspective of Electrocatalytic CO₂ Reduction for Renewable Carbonaceous Fuels and Chemicals

Abstract

The worldwide unrestrained emission of carbon dioxide (CO₂) has caused serious environmental pollution and climate change issues. For the sustainable development of human civilization, it is very desirable to convert CO₂ to renewable fuels through clean and economical chemical processes. Recently, electrocatalytic CO₂ conversion is regarded as a prospective pathway for the recycling of carbon resource and the generation of sustainable fuels. In this review, recent research advances in electrocatalytic CO₂ reduction are summarized from both experimental and theoretical aspects. The referred electrocatalysts are divided into different classes, including metal-organic complexes, metals, metal alloys, inorganic metal compounds and carbon-based metal-free nanomaterials. Moreover, the selective formation processes of different reductive products, such as formic acid/formate (HCOOH/HCOO^-), monoxide carbon (CO), formaldehyde (HCHO), methane (CH₄), ethylene (C₂H₄), methanol (CH₃OH), ethanol (CH₃CH₂OH), etc. are introduced in detail, respectively. Owing to the limited energy efficiency, unmanageable selectivity, low stability, and indeterminate mechanisms of electrocatalytic CO₂ reduction, there are still many tough challenges need to be addressed. In view of this, the current research trends to overcome these obstacles in CO₂ electroreduction field are summarized. We expect that this review will provide new insights into the further technique development and practical applications of CO₂ electroreduction.