Defects and Transport Properties in <scp> <scp>TiNb</scp> </scp> ₂ <scp> <scp>O</scp> </scp> ₇

Abstract

The electrical conductivity of TiNb 2 O 7 was characterized as a function of temperature, and . The total conductivity was independent of in the low oxygen partial pressure regime, while a dependency of was observed at higher oxygen partial pressures. The conductivity increased with increasing under oxidizing conditions below 700°C. Mixed electronic and protonic conduction was indicated by H/D isotope exchange and transport number measurements. A defect model based on interstitial type of hydration was established and fitted to the conductivity data allowing for determination of physicochemical parameters of hydration and electron migration.