Hydrogen in transition metal doped transparent conductive oxide SnO₂

Abstract

First-principles, thermodynamic, and kinetic Monte Carlo methods are used to study the behavior of hydrogen defects in doped-tin oxides. The calculated results indicate that Mo-, W-, Nb-, F-doped SnO2 are the best doped-tin oxides at reducing hydrogen solubility in their matrices. We expect these oxides also to be the best for removing hydrogen via proton reduction and hydrogen evolution from their surfaces due to the relatively high electron concentration they can have. Especially, W-doped is also found to perform best as a hydrogen blocker at all temperature range due to its ability to block hydrogen diffusion in the form of substitutional defect at low-temperature regime around 600K, and its nature to increase tin cation vacancies blocking hydrogen diffusion at high-temperature regime around 1200K. The computational approach developed here can accelerate the design of insulating materials where hydrogen reactions and proton transport are important.