Unveiling and utilizing the reconstructing dynamics on nanoporous Ag-Bi for CO2 electroreduction

Abstract

The reconstruction of catalysts during electrochemical reactions has become an unavoidable issue for higher catalytic activity and the intrinsic mechanism. Herein the reconstruction that amorphous Bi shell forming onto nanoporous AgBi during CO2ER is regulated by potential, and the optimal reconstruction potential is confirmed to be − 1.05 V. The surface reconfiguration and catalytic property conversion along with the reconstruction are identified via in-situ electrochemical and spectroscopic characterizations. The reconstructed catalyst achieves a Faradaic efficiency of 94 %, partial current density of 19.75 mA•cm−2, and wonderful durability, thanks to the special nanoporous core-shell structure with abundant defects and a efficient electron transport. Furthermore, computational simulation manifests that Bi atoms on the ligament surface are more capable to activating CO2 than Ag atoms. This investigation introduces one method to elucidate the real state of catalysts and proposes a novel strategy for designing electrochemical catalysts with high activity and durability by atomic scale reconstruction.