# In Situ Visualization of Electron Beam‐Driven High‐Entropy Alloy Crystallization

## TL;DR

Researchers used electron microscopy to visualize how electron beams help create uniform high-entropy alloy nanoparticles with controlled shape and composition.

## Contribution

The study reveals an athermal crystallization mechanism using electron beams to produce compositionally uniform HEA nanoparticles.

## Key findings

- Electron beam-induced crystallization forms single-phase fcc HEA nanoparticles with cuboidal morphology.
- The process suppresses phase segregation and elemental clustering by limiting atomic mobility.
- The method offers a scalable route for low-temperature synthesis of uniform multielement alloys.

## Abstract

Achieving compositionally uniform high‐entropy alloy (HEA) nanoparticles via reduction‐based synthesis remains challenging due to variations in elemental reduction, diffusion, and phase stability. Using in situ transmission electron microscopy (TEM), this study visualizes the electron beam–induced crystallization of amorphous high‐entropy glycerolate (HE‐glycerolate) films composed of Mg, Mn, Co, Ni, and Zn. The transformation proceeds through phase separation, radiolytic reduction, and localized atomic rearrangement, producing single‐phase face‐centered cubic (fcc) HEA nanoparticles with uniform cuboidal morphology and dominant {100} facets. Compared to thermal annealing, the electron beam pathway offers finer control over composition and morphology by limiting atomic mobility and preventing phase segregation or Co/Ni clustering. This displacement‐driven, athermal process enables gradual, diffusion‐limited crystallization within confined regions, resulting in well‐defined, compositionally homogeneous alloys. The study reveals the mechanism of electron beam‐driven crystallization of HEA nanoparticles and establishes a broader principle that controlling atomic mobility is key to achieving stable, multielement solid solutions. The insights gained, highlighting the role of confined atomic mobility, offer a valuable foundation for designing new low‐temperature synthesis routes for uniform HEA materials with controlled phase and morphology, and inform the development of scalable processing strategies for homogeneous multicomponent systems.

In situ transmission electron microscopy visualizes the electron beam‐driven crystallization of amorphous multielement glycerolate film into single‐phase high‐entropy alloy (HEA) nanoparticles. The athermal process proceeds via radiolytic reduction and localized atomic rearrangement, forming compositionally uniform, cuboidal face‐centered cubic HEA nanostructures while suppressing elemental segregation through diffusion‐limited crystallization.