Molecular trapdoor mechanism of In-SSZ-13(MP) holds promise for selective electrochemical reduction of CO2 at low concentrations

Abstract

The unique molecular trapdoor mechanism of chabazite zeolites provides an ideal platform for CO2 integrative adsorption and conversion. Herein, a mesoporous In-SSZ-13(MP) catalyst was successfully synthesized through desiliconization combined with anchoring uniformly dispersed indium (In) active sites, which achieved the highest formate Faraday efficiency (FEHCOO-) of 92.0 % and a formate partial current density (jHCOO-) of 133.3 mA cm−2 for electrochemical CO2 reduction reaction (CO2RR) at a moderate overpotential of 0.8 V. Experimental results combined with DFT calculations reveal the reaction mechanism of In-SSZ-13(MP) electrocatalytic reduction of CO2: as the only channel into the In-SSZ-13(MP) crystal, the gatekeeper (cation, In3+) in eight-membered ring (8MR) deviates from its original position induced by CO2 molecule, then CO2 poured into CHA cage and fully reacted with uniformly distributed indium active sites.