 the working mechanism of several low-cost electrocatalyst materials is still arguable. Here the authors show a model FE-MN-NC catalyst where the oxygen reduction preferentially takes place on FE-3 sites with the intermediate spin state, T2G4EG1, caused by the adjacent MN-N moieties. This article was authored by Guichiyang, Joeshu, Pengfei Yuan, and others.