Electrochemically stable frustrated Lewis pairs on dual-metal hydroxides for electrocatalytic CO 2 reduction.

The sluggish kinetics of CO 2 activation and reduction severely limit the energy conversion efficiency of electrocatalytic CO 2 reduction into fuels. Here, ZnSn(OH) 6 with an alternating arrangement of Zn(OH) 6 and Sn(OH) 6 octahedral units and SrSn(OH) 6 with an alternating arrangement of SrO 6 and Sn(OH) 6 octahedral units were adopted to check the effects of frustrated Lewis pairs (FLPs) on electrochemical CO 2 reduction. The FLPs were in situ electrochemically reconstructed on ZnSn(OH) 6 by reducing the electrochemically unstable Sn-OH to Sn-oxygen vacancies (Sn-O Vs ) as a Lewis acid site, which are able to create strong interactions with the adjacent electrochemically stable Zn-OH, a Lewis base site. Compared to SrSn(OH) 6 without FLPs, the higher formate selectivity of ZnSn(OH) 6 originates from the strong ability of FLPs to capture protons and activate CO 2 via the electrostatic field of FLPs triggering better electron transfer and strong orbital interactions under negative potentials. Our findings may guide the design of electrocatalysts for CO 2 reduction with high catalytic performances.