Highly efficient electrochemical reduction of CO(2) to CH(4) in an ionic liquid using a metal–organic framework cathode

Highly efficient electrochemical reduction of CO(2) to CH(4) is of great importance, but is challenging. Herein, Zn–1,3,5-benzenetricarboxylic acid metal–organic frameworks (Zn–BTC MOFs) deposited on carbon paper (CP) were used as cathodes in electrochemical reduction of CO(2) using ionic liquids (ILs) as the electrolytes, which was the first work on combination of a MOF electrode and an pure IL electrolyte in the electrochemical reduction of CO(2). It was found that the efficiency of the reaction depended strongly on the morphology of the Zn-MOFs. Compared with the commonly used metal electrodes, the electrochemical reaction showed much higher selectivity to CH(4) and current density, and the overpotentials for CH(4) is much lower. The excellent combination of the MOF cathodes and ILs opens a way for reduction of CO(2) to CH(4) effectively.