Lattice Hydrogen Participation and Mass Transport Acceleration Improve CO2 Electroreduction to C2 Products
He Zhang , Simeng Liu , Chao Zhang , Wei Liu , Hongliang Dong , Zhaolin Shi , Han Xu , Jinbiao Liu , Dingsheng Wang , Jiqing Jiao* , Mingbin Gao* , Tongbu Lu*
CO2 electroreduction operated at high current densities typically face the critical issues of CO2 depletion and competing reactions. Here we prepared CuH branched nanosheets stabilized with holmium single atoms (HoSA-CuH). Finite-element analyses show that the branched HoSA-CuH structure could accelerate mass transport and alleviate CO2 depletion under high current densities. In situ spectroscopies and theoretical calculations reveal that the introduced Ho single atoms increase the electron density at Cu surface, which is conducive to CO2 enrichment and activation. Deuterium isotope labeling experiments confirm that the lattice hydrogen in CuH participate in the reaction, thereby lowering the energy barrier for the rate-determining step in C–C coupling. Therefore, the selectivity for C2+ over HoSA-CuH is above 80% under 700–1200 mA cm−2 and C2 products account for 95% of all the C2+ products. Compared with the best-performing catalysts reported thus far, HoSA-CuH displays the broadest current density range for high FEC2.
https://doi.org/10.1002/anie.202518519
