  Engineering strain critically affects the properties of materials and has
extensive applications in semiconductors and quantum systems. However, the
deployment of strain-engineered nanocatalysts faces challenges, particularly in
maintaining highly strained nanocrystals under reaction conditions. Here, we
introduce a morphology-dependent effect that stabilizes surface strain even
under harsh reaction conditions. Employing four-dimensional scanning
transmission electron microscopy (4D-STEM), we discovered that core-shell Au@Pd
nanoparticles with sharp-edged morphologies sustain coherent heteroepitaxial
interfaces with designated surface strain. This configuration inhibits
dislocation due to reduced shear stress at corners, as molecular dynamics
simulations indicate. Demonstrated in a Suzuki-type cross-coupling reaction,
our approach achieves a fourfold increase in activity over conventional
nanocatalysts, owing to the enhanced stability of surface strain. These
findings contribute to advancing the development of advanced nanocatalysts and
indicate broader applications for strain engineering in various fields.
