Preserving Surface Strain in Nanocatalysts via Morphology Control

TL;DR

This paper demonstrates a morphology-dependent strategy to stabilize surface strain in nanocatalysts, significantly enhancing their catalytic activity and stability under reaction conditions, with potential broad applications.

Contribution

It introduces a novel morphology control method that maintains surface strain in nanocatalysts under harsh conditions, verified by advanced microscopy and simulations.

Findings

Core-shell Au@Pd nanoparticles with sharp edges sustain surface strain.

Strain stabilization leads to fourfold increase in catalytic activity.

Dislocation formation is inhibited by morphology-induced shear stress reduction.

Abstract

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.