Quantitative analysis of atomic migration in lithium-ion conducting oxide solid electrolytes

Abstract

Direct observation of intrinsic atom migration inside bulk materials is crucial for understanding the ion-conducting property; however, microscopy experiments remain challenging. Here, intrinsic atom migration in bulk lithium-ion conductor La2/3–xLi3xTiO3 was investigated by using aberration-corrected transmission electron microscopy. The atomic migration was triggered by high-energy electron beam irradiation. Through quantitative analysis of high-angle annular dark-field image sequences and estimation of random errors using the 3σ criterion, the subtle contrast variation caused by single atom migration was extracted, in which the validity was further confirmed by image simulations. It provides a simple and feasible methodology for investigating the mechanism of atomic migration in bulk materials.