Activation of Main-Group Antimony Atomic Sites for Oxygen Reduction Catalysis.

The catalytic activity of main-group metal is hard to promote because of the intrinsic lack of host d orbitals available to be combined. Herein, under the guidance of theoretical predictions, we find atom-dispersed antimony sites (Sb-N 4 moieties) can be activated to achieve high oxygen reduction reaction (ORR) activity using a functional group regulation strategy. Correspondingly, we manage to synthesize a main-group Sb single-atom catalysts (SACs) that comprises Sb-N 4 active moieties functionalized by epoxy groups in the second microenvironment and incorporated in N-doped graphene (Sb 1 /NG(O)). The electron-rich epoxy group can adjust the electronic structure of Sb-N 4 active moieties, thereby optimizing the adsorption of the intermediate. The Sb SACs are comparable to industrial Pt/C under alkaline conditions. This discovery provides new opportunities to manipulate and improve the catalytic activity of main-group-element electrocatalysts.