Heterogeneous Electrochemical Carbon Dioxide Reduction in Aqueous Medium Using a Novel N4-Macrocyclic Cobalt Complex.

Molecular catalysts represent an exceptional class of materials in the realm of electrochemical carbon dioxide reduction (CORR), offering distinct advantages owing to their adaptable structure, which enables precise control of electronic configurations and outstanding performance in CORR. This study introduces an innovative approach to heterogeneous electrochemical CORR in an aqueous environment, utilizing a newly synthesized N4-macrocyclic cobalt complex generated through a dimerization coupling reaction. By incorporating the quaterpyridine moiety, this cobalt complex exhibits the capability to catalyze CORR at low overpotentials and reaches near-unity CO production across a wide potential range, as verified by the online mass spectrometry and in situ attenuated total reflectance-Fourier transform infrared spectroscopy. Comprehensive computational models demonstrate the superiority of utilizing quarterpyridine moiety in mediating CO conversion compared to the counterpart. This work not only propels the field of electrochemical CORR but also underscores the promising potential of cobalt complexes featuring quaterpyridine moieties in advancing sustainable CO conversion technologies within aqueous environments.