The mechanism of nanoparticle precipitation induced by electron irradiation in transmission electron microscopy

TL;DR

This paper explains how electron irradiation in transmission electron microscopy induces the formation of Ru nanoparticles in doped silica by creating electric fields that lower nucleation barriers and accelerate particle precipitation.

Contribution

It introduces a new mechanism involving electric fields and ion drift to explain nanoparticle formation under electron irradiation in TEM.

Findings

Electric fields from irradiation reduce nucleation energy barriers.

Ion drifting accelerates nanoparticle precipitation.

A new interpretative mechanism for TEM-induced nanoparticle formation.

Abstract

Ru nanoparticles (NPs) can precipitate in Ru doped SiO2 amorphous thin films, triggered by electron irradiation in (scanning) transmission electron microscope ((S)TEM). A new mechanism was introduced to interpret the formation of metal NPs in (S)TEM. The induced electric field by electron irradiation, which originates from charging due to ionizations and excitations of atom electrons, can reduce the Gibbs free energy barrier for nucleation of metal particles. Furthermore, the directional ion drifting driven by the electric forces may accelerate the kinetic process of metal particle precipitation.