Oxygen Activation on Carbon-coated Iron Nanoparticles

Abstract

This work explores the feasibility of molecular oxygen activation and dissociation on the sp²hybridized carbon surface of carbon-coated iron nanoparticles. Using density functional theory with a generalized gradient approximation, we elucidate the geometry and electronic structure of these nanoparticles, highlighting the nature of the C-Fe binding interactions and the resulting modifications to the carbon surface electronic states. The enhanced catalytic activity of carbon induced by the underlying iron core is attributed to core-shell electronic interactions within the nanoparticles. Activation of molecular oxygen to superoxo and peroxo species was investigated using the nudged elastic band method, with electron transfer processes analyzed in detail and linked to the core-shell characteristics of the system. Additionally, we examined the effects of nitrogen doping in the carbon shell on the structural and electronic properties of the nanoparticles.Potential degradation pathways, including parasitic reactions during oxygen activation, were also identified. This study offers new theoretical insights into the functional behavior of Fe-C-N catalysts.