Modulating Electronic Structure of Cu-Based MOF via Ni Doping for Efficient CO2 Electroreduction to C2+ Products

Abstract

Copper-based catalysts were used in electrochemical CO2 reduction reactions (CO2RR) to provide a sustainable way to convert CO2 into valuable chemicals, but achieving high selectivity for multi-carbon (C2+) products such as ethylene remains challenging. Herein, we report a series of Ni-modified copper-based metal organic frameworks (MOFs) catalysts were synthesized by solvothermal method and subsequently subjected to calcination to obtain its derivatives. Among the prepared catalysts, CuNi-2 catalyst achieved a high Faradaic efficiency of 55.56% for C2+ and 32.35% for ethylene at -1.0 V vs. RHE, along with excellent stability over 40 h of continuous operation. Systematic characterization revealed that the introduction of Ni modulated the electronic structure of Cu, stabilizes Cu+ active species, and enriches the surface coverage of *CO intermediates, thereby promoting C-C coupling (a critical step toward C2H4 formation). Additionally, the porous MOFs-derived structure facilitates mass transport and confines reactive intermediates, further boosting ethylene selectivity. This work provides a bimetallic electronic modulation strategy offers a promising pathway for designing efficient Cu-based electrocatalysts toward high-value C2+ products.