Conformal Shell Amorphization of Nanoporous Ag-Bi for Efficient Formate Generation.

: Simultaneous attainments of high conductivity and superior catalysis are major challenges for amorphous electrocatalysts in carbon dioxide (CO2) electroreduction (CO2ER) at high overpotential. In this study, one protocol is first demonstrated to drive a shell amorphization of nanoporous Ag-Bi catalyst (a-NPSB) with the spatially interconnected ligament during the initial stage of CO2ER. This newborn a-NPSB bestows the outstanding catalysis, evidenced by Faradaic efficiency of 88.4% for formate production at -1.15 V vs RHE, and specific current density of 321 mA/mg that is 2 times as that on the Bi nanoparticles. The unique catalysis is considered as the collective contribution of the conductive ligament internally and amorphous Bi2O3 shell with 3 nm thick externally. Simultaneously obtaining the conductivity of inner metals and the catalysis of amorphous shell will pave a new avenue for designing robust electrode during electrochemical reaction.