Majority charge carrier reversal and its effect on thermal and electron transport in xV2O5-(1 − x) As2O3 glasses

► Vanadate glasses in the system, xV2O5-(1 − x) As2O3, containing up to 42 mol% As2O3 were studied. ► V provides polarons (SP) and As provides bipolarons (SBP) for electrical conduction. ► SP hopping is the main mechanism of electrical conduction with minimal contribution from BP. ► Thermopower is negative for > 73 mol% V2O5 glasses and positive for others indicating influence of BPs. ► There is a change in the majority charge carrier around 70 mol% V2O5.