Oxygen Vacancy-Enriched FeOx Nanoparticle Electrocatalyst for the Oxygen Reduction Reaction

FeO x electrocatalysts for the oxygen reduction reaction were prepared via one-step synthesis using electron impact with cold plasma as the electron source. Given the low operation temperature, FeO x by plasma technology showed a smaller particle size than that prepared via conventional calcination. Notably, electron impact produced more oxygen vacancies and a larger surface area on FeO x , which increased active sites and electronic conductivity, than plasma. Electrochemical investigations indicated that FeO x prepared by plasma exhibited remarkable oxygen reduction reaction activity toward the four-electron electrochemical reduction of oxygen. The results demonstrated that this facile fabrication method is a promising route for developing cost-effective and high-performance catalysts to be used in electrochemical applications.