Augmented CO2 utilization for acidic industrial-level CO2 electroreduction to near-unity CO

Electrochemical reduction of CO2 represents an environmental-friendly process that could alleviate the environmental and energy crisis by eliminating greenhouse gases and generating value-added chemicals. However, industrial-level CO2 reduction to CO suffers from low CO2-conversion efficiency. To address this issue, this work proposes to use acidic electrolytes to avoid carbonate/bicarbonate salt precipitation, and shell for local CO2 adsorption to improve its utilization and thus facilitate electroconversion. An Ag-based metal-organic framework (MOF) is hybridized with Ag, which exhibits near-unity selectivity to CO at an industrial-level current density (500 mA cm−2) in acidic media, robust electrochemical stability (100 hours) and more importantly, high CO2 conversion efficiency of 42.5%. Fundamentally, CO2 molecules are activated by Ag-MOF via atop adsorption of *CO after uptake by the porous organic complexes. The extraordinary performance originates from multi-scale regulation of CO2 transport from the gas-diffusion layer to the local CO2 adsorption shell near the atomic Ag active center of Ag-MOF.