Site?Specific Axial Oxygen Coordinated FeN ₄ Active Sites for Highly Selective Electroreduction of Carbon Dioxide

Regulating the coordination environment via heteroatoms to break symmetrical electronic structure of M-N4 active sites provides a promising route engineer metal-nitrogen-carbon catalysts for electrochemical CO2 reduction reaction. However, it remains challenging realize site-specific introduction at atomic level due their energetically unstable nature. Here, this paper reports facile using an oxygen- and nitrogen-rich metal–organic framework (MOF) (IRMOF-3) as precursor construct Fe-O Fe-N chelation, simultaneously, resulting in atomically dispersed axial O-coordinated FeN4 site. Compared without O coordination, formed FeN4-O exhibit much better catalytic performance toward CO, reaching maximum FECO 95% ?0.50 V versus reversible hydrogen electrode. To best authors’ knowledge, such exceeds that existing Fe-N-C-based derived from sole N-rich MOFs. Density functional theory calculations indicate O-coordination regulates binding energy intermediates reaction pathways, smoother desorption CO increased competitive production.