Electrocatalytic CO₂ reduction into controllable clean syngas (H₂ and CO) by using clean electric energy is an environment-friendly strategy for the cycle of carbon resources. However, there are still some challenges in this process, such as low current density and high onset potential. In this work, ZIF-8 is used as the precursor to adjust the ratio of metal Ni and Cu to control the composition of syngas (H₂/CO 0.6:1–8:1). When metal Ni and Cu are both present, the onset potential can be effectively reduced, and the limiting current density would increase at the same time. Through subsequent experimental characterization and analysis, the catalyst of Ni Cu-1 effectively reduces the onset potential and increases the limiting current density. What’s more, the superior CO₂ electroreduction performance is attributed to the high binding energy of pyridine N in Ni NC, and the introduction of Cu in Ni Cu-1 is beneficial to the generation of syngas with adjustable composition. The research provides a feasible method for electrocatalytic CO₂RR to reasonably utilize H₂ competition reaction and regulate the proportion of syngas.

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