Golden Single‐Atom Alloys Selectively Boosting Oxygen Reduction and Methanol Oxidation

Abstract Engineering electrocatalysts at a single‐atomic site can enable unprecedented atomic utilization and catalytic activity, yet it remains challenging in multimetallic active centers to simultaneously achieve high catalytic selectivity and stability. Herein, the atomic design and control of golden single‐atom alloys (PdAu 1 and PtAu 1 SAAs) based on fully ordered PdBi and PtBi matrixes is presented, serving as highly selective, active, and stable cathode and anode electrocatalysts, respectively, to trigger direct methanol fuel cell (DMFC). The octahedral PdAu 1 SAA exhibits ultrahigh mass‐activity of 5.37 A mg Pd + Au −1 without noticeable decay for 12 0000 cycles toward oxygen reduction. While PdAu 1 SAA is inactive for methanol oxidation, PtAu 1 SAA exhibits an ultrahigh mass‐activity of 28.59 A mg Pt + Au −1 . The selective electrocatalysts drive a practical DMFC with a high‐power density of 155.0 mW cm −2 . Density functional theory calculations reveal the desired regulation of selectivity via reducing the energy barrier for potential‐determining steps (PDS) of * OH to H 2 O and * HCOO to CO 2 . This work provides a general strategy to engineer multimetallic alloys at the atomic level, advancing the development of high‐performance electrocatalysts.