|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Computational Thermodynamics and Kinetics
||Impact of Varying Oxygen Stoichiometry on Electrochromic Behavior in WO3
||Wennie Wang, Anderson Janotti, Chris G. Van de Walle
|On-Site Speaker (Planned)
Tungsten trioxide (WO3) is most notably used as an electrochromic material in electrically tintable smart windows. As an electrochromic material, doping causes a change from transparent to blue and a drop in transmission of near-IR, making it useful for energy efficiency applications. Tungsten trioxide is well known to exist in stoichiometries with deficient or excess oxygen. Oxygen vacancies have been invoked as a source of electrochromism, whereas excess oxygen has been proposed to lead to irreversible cycling when doping. However, the precise mechanisms by which oxygen deficiency or excess influence electrochromic behavior have remained elusive. We investigate oxygen vacancies and interstitials in monoclinic WO3 using density functional theory. We study the stability of such defects, their interaction with dopant species, and migration barriers for diffusion. Finally, we compare our findings with experiment to understand the mechanisms that govern electrochromism.
This work is supported by DOE and NSF.
||Planned: A print-only volume