Defect formation in In2O3and SnO2: a new atomistic approach based on accurate lattice energies

Qing Hou,Alexey A Sokol,Tomas Lazauskas,C Richard A Catlow,Scott M Woodley,David Mora-Fonz,John Buckeridge

doi:10.1039/c8tc04760j

Abstract

A new consistent interatomic force field for In2O3and SnO2.

Highlights

The combination of high optical transparency and high electrical conductivity in transparent conducting oxides (TCOs) results in the class of materials being widely used in many fields, including solar cells, liquid crystal displays, electrochromic plating and smart windows.[1,2,3] The most commonly used n-type TCO materials are SnO2 and In2O3, which tend to be oxygen deficient due to the appearance of oxygen vacancies,[4,5,6,7] and tin-doped In2O3
The new model was obtained by empirical fitting, using the General Utility Lattice Package (GULP) code, to calculate lattice parameters, lattice energy, and static and high-frequency dielectric constants and gave a better agreement with the experimental data compared to earlier work, as shown in Tables 2 and 3
We have demonstrated that our interatomic potential model can give defect formation energies comparable with those obtained using Density Functional Theory (DFT)

Summary

Introduction

The combination of high optical transparency and high electrical conductivity in transparent conducting oxides (TCOs) results in the class of materials being widely used in many fields, including solar cells, liquid crystal displays, electrochromic plating and smart windows.[1,2,3] The most commonly used n-type TCO materials are SnO2 and In2O3, which tend to be oxygen deficient due to the appearance of oxygen vacancies,[4,5,6,7] and tin-doped In2O3 (indium tin oxide, ITO). Accurate modelling of intrinsic and extrinsic defects is needed to understand the source of conductivity. Computational techniques based on interatomic potentials, in contrast, are well suited to explore such systems, but require sufficiently accurate and transferable parameterisation. Previous work on the parameterisation of interatomic potentials suffered from a number of problems related to transferability and/or accuracy in the reproduction of essential physical properties of both parent SnO2 and In2O3 compounds. We demonstrate the first transferable interatomic potential model that reproduces well the physical properties of SnO2 and In2O3 including their dielectric response and lattice energies. We apply our methodology to develop a consistent and reliable set of models for the defect structure of the materials

Objectives

Methods

Results

Conclusion