Sulfur-induced dynamic reconstruction of iron-nitrogen species for highly active neutral oxygen reduction reactions

The neutral oxygen reduction reaction (ORR) has attracted tremendous attention for its broad prospects in next-generation power storage systems. However, the extremely sluggish cathodic reaction process and the limited cognition of the reaction mechanism greatly hinder its practical application. Here, we demonstrate a dynamic reconstruction behavior induced by sulfur of the iron-nitrogen (Fe-N x ) species in neutral solution. Our developed FeS 1 N 3 -OH configuration effectively optimizes the reaction kinetics by regulating the adsorption energy of oxygen intermediates for central catalytic sites. Consequently, this structure exhibits over 363% enhancement in ORR mass activity compared to the pristine FeN 4 sites under neutral electrolyte. Moreover, a neutral zinc-air battery assembled with this electrocatalyst reached an ultrahigh peak power density (81.2 mW cm −2 ), robust stability (more than 100 h) as well as superior tolerance to extreme environments (operating between −20 °C and 60 °C), representing a critical breakthrough for neutral ORR exploration and application.