Electro-Chemical Reduction of Carbon Dioxide into Ethylene: Catalyst, Conditions and Mechanism

Electrochemical reduction of carbon dioxide into ethylene not only can alleviate the greenhouse effect but also obtain ethylene as one of the high value-added petrochemicals. The article reviews recent advances in the field of carbon dioxide electro-catalytic reduction to produce ethylene, and mainly focus on the electro-catalysts for the reduction of carbon dioxide into ethylene. Copper-based catalyst is an active ingredient for highly selective generation of ethylene. Doping, modifying or decorating copper-based catalyst can increase the stability and activity of the catalyst while maintaining the high selectivity of the catalyst for ethylene. The mechanism for ethylene formation under electro-catalytic conditions and the effect of reaction conditions on ethylene selectivity are also included. Three adsorptive states of carbon dioxide on the surface of catalyst and the mechanism of ethylene formation on the Cu (100) crystal face are briefly described. The effects of electrode potential, temperature, pressure, the composition of electrolyte and pH on ethylene selectivity are also considered. Finally, the issues in the field of catalyst development and research for reducing carbon dioxide into ethylene are summarized and prospected.