Electrochemical Reactive Capture of Carbon Dioxide Using an Amine Sorbent and a Homogeneous Cobalt Electrocatalyst

The electrochemical reactive capture of CO 2 ( e -RCC) process, in which the capture of CO 2 from industrial point sources is integrated with electrochemical conversion into valuable fuels and chemical feedstocks, is an ambitious technological frontier in energy science and industrial waste upcycling. We present an e -RCC system to capture and convert CO 2 to CO using amines as sorbents and molecular cobalt electrocatalysts with pyridyldiimine-based ligands. Sparging dilute CO 2 through water/acetonitrile electrolyte solutions containing n -butylamine and the cobalt catalyst enables the electroreduction of CO 2 with enhanced activity and selectivity. Even at flue-gas concentrations of CO 2 (5% v/v CO 2, balance N 2 ), the presence of n -butylamine in the electrolyte enables the reduction of CO 2 to CO with 3-fold higher activity (TOF cat ∼3.3 × 10 4 s –1 ) compared to the catalyst system without amine. This study serves as a proof of concept for direct electrochemical reduction of CO 2 from dilute streams using an amine-based e -RCC process.