Cascade Conversion of CO2 to Ethylene Carbonate under Ambient Conditions

Ethylene carbonate (EC) is the simplest cyclic carbonate with great industrial significance, most importantly as the vital electrolyte component for lithium-ion batteries. Its conventional synthesis generally involves the use of toxic precursors and requires elevated temperatures and pressures. Herein, we propose a cascade catalytic route for converting CO2 to EC under ambient conditions. Such a hybrid reaction scheme consists of the electrochemical reduction of CO2 to ethylene catalyzed by copper in a membrane electrode assembly reactor, the bromine-mediated conversion of ethylene to bromoethanol catalyzed by WO3 nanoarrays grown on carbon cloth, and the reaction between bromoethanol and CO2 to form EC. By separately optimizing individual catalytic steps and then integrating them together in series, we achieved the conversion of CO2 to EC at a good yield under room temperature and atmospheric pressure. Our study also represents the first demonstration about the successful synthesis of organic carbonates from CO2 as the exclusive carbon source.