Three-dimensional atomic interface between metal and oxide in Zr-ZrO2 nanoparticles

TL;DR

This study reveals the three-dimensional atomic structure of metal-oxide interfaces in zirconium-zirconia nanoparticles using atomic-resolution electron tomography, providing new insights into their atomic arrangement and defects.

Contribution

It introduces a novel 3D atomic imaging technique for metal-oxide interfaces, overcoming previous limitations of 2D imaging and revealing detailed interface structures.

Findings

Interfaces are broken in coherency and symmetry

Presence of Zr vacancies and nano-pores at the interface

Provides direct 3D atomic evidence of interface structure

Abstract

Metal-oxide interfaces with poor coherency have unique properties comparing to the bulk materials and offer broad applications in the fields of heterogeneous catalysis, battery, and electronics. However, current understanding of the three-dimensional (3D) atomic metal-oxide interfaces remains limited because of their inherent structural complexity and limitations of conventional two-dimensional imaging techniques. Here, we determine the 3D atomic structure of metal-oxide interfaces in zirconium-zirconia nanoparticles using atomic-resolution electron tomography. We quantitatively analyze the atomic concentration and the degree of oxidation, and find the coherency and translational symmetry of the interfaces are broken. Moreover, we observe porous structures such as Zr vacancies and nano-pores and investigate their distribution. Our findings provide a clear 3D atomic picture of metal-oxide interface with direct experimental evidence. We anticipate this work could encourage future studies on fundamental problems of oxides such as interfacial structures in semiconductor and atomic motion during oxidation process.