Corrosion of nanoparticles during electrocatalysis, such as oxygen reduction reaction (ORR), occurs at the nanoscale and is vital for catalyst stability. Here, using liquid cell (LC) transmission electron microscopy (TEM), we study the corrosion process of palladium@platinum (Pd@Pt) core-shell octahedra in real time and reveal that both the static local strain and the evolving curvature synergistically control the nanoscale corrosion kinetics. Specifically, in locations with tensile strain and high local curvature, the etching process is much faster. Density functional theory (DFT) calculation suggests that the dissolution potential of the Pd nanocrystal decreases as the strain increases; meanwhile, Pd atoms tend to be corroded more easily on a surface under tensile strain than on one under compressive strain. With these insights on the corrosion mechanism at the nanoscale, we subsequently designed and synthesized nanoparticles with smaller strain, and these showed higher durability in both an in situ LC study and an ex situ ORR stability test.

电催化过程中纳米颗粒的腐蚀（例如氧还原反应（ORR））在纳米级发生，对于催化剂的稳定性至关重要。在这里，我们使用液池（LC）透射电子显微镜（TEM），实时研究了钯@铂（Pd @ Pt）核壳八面体的腐蚀过程，并揭示了静态局部应变和演化曲率可以协同控制纳米级腐蚀动力学。具体而言，在具有拉伸应变和高局部曲率的位置，蚀刻过程要快得多。密度泛函理论（DFT）的计算表明，Pd纳米晶体的溶解电势随应变的增加而降低。同时，Pd原子在拉伸应变下比在压缩应变下更容易腐蚀。原位LC研究和易地ORR稳定性测试。