Investigation of the electrostatic potential of a grain boundary in Y-substituted BaZrO3 using inline electron holography

TL;DR

This study uses inline electron holography to measure and analyze the electrostatic potential across a Y-substituted BaZrO3 grain boundary, revealing the roles of vacancies and atomic density reduction.

Contribution

It introduces inline electron holography for direct measurement of grain boundary potentials in Y-doped BaZrO3, combining experimental and theoretical insights.

Findings

Measured a grain boundary potential of -1.3 V

Barium vacancies are primary contributors to the potential well

Reduced atomic density also influences the electrostatic potential

Abstract

We apply inline electron holography to investigate the electrostatic potential across an individual BaZr0.9Y0.1O3 grain boundary. With holography, we measure a grain boundary potential of -1.3 V. Electron energy loss spectroscopy analyses indicate that barium vacancies at the grain boundary are the main contributors to the potential well in this sample. Furthermore, geometric phase analysis and density functional theory calculations suggest that reduced atomic density at the grain boundary also contributes to the experimentally measured potential well.