CO₂-philic NiNC nanocatalyst regulation mediated by imidazole-based ZIF for high-efficiency CO₂ electroreduction

Developing highly efficient catalysts for carbon dioxide reduction reaction (CO₂RR) to convert CO₂ into carbon-based chemicals and reduce anthropogenic carbon emissions is desirable but challenging. In this work, a high-activity NiNC-2mIM catalyst has been developed via pyrolysis of 2-methylimidazole (2mIM) Ni-zeolite-imidazolate-framework (ZIF) precursor, it exhibits excellent performance for CO₂ reduction producing carbon monoxide (CO), with Faradaic efficiency for CO (FE_CO) of about 98% and a current density of 55 mA·cm⁻² at −1.0 V (vs. reversible hydrogen electrode (RHE)), outperforming the investigated NiNC-IM and NiNC-2eIM (derived from imidazole Ni-ZIF precursor and 2-ethylimidazole Ni-ZIF precursor, respectively) in this work and many previously reported Ni-based nanocatalysts. Mechanism studies demonstrate that 2-methylimidazole ligand induces higher content of pyridinic N species in the NiNC-2mIM catalyst, which enhances the affinity for CO₂ and provides low-polarity and high-activity Ni–N motif for CO₂RR. This work develops a novel imidazole-based ZIF mediated regulation strategy for engineering pyridinic N-rich N-doped carbon supported Ni nanocatalyst to highly efficiently catalyze CO₂ reduction producing CO.