Customizing the Crystal Facet of Carbon-Encapsulated Nickel Catalyst for Selective and Durable Electrocatalytic CO2 Reduction to CO

Abstract

Carbon-supported non-noble metal-based catalysts display remarkable catalytic activity and cost-effectiveness in electrochemical CO₂ reduction reaction (eCO₂RR). However, precise control of the crystal facet of metal catalysts and prevention of deactivation caused by agglomeration remain challenges. Herein, a novel dual-function customized strategy is presented for the preparation of the N-doped carbon-supported Ni-based porous catalyst with carbon-encapsulated Ni(111) nanoparticles (Ni(111)@C-NDPC), through carbonizing the self-assembly of protein–Ni-ions networks and ethylenediaminetetraacetic acid (EDTA)-chelated Ni-ions (EDTA–Ni). High exposure of the (111) surface of carbon-encapsulated nickel nanoparticles is achieved through strong coordination between EDTA–Ni, thereby synergistically integrating the advantages of highly active Ni(111) and stable carbon-encapsulated structure formed by protein–Ni-ions networks. Theoretical calculations reveal that Ni(111) facilitates the formation of *COOH and inhibits the hydrogen evolution reaction. The as-prepared Ni(111)@C-NDPC electrocatalyst exhibits an excellent CO Faradaic efficiency (FE_CO) of 96.3% and stability over 50 h while maintaining FE_CO above 90% in a wide current density range of 50–300 mA cm^–2. This work provides a new strategy for precisely customizing highly selective and durable carbon-supported metal eCO₂RR electrocatalysts.