In TiO2thin films, the charge carriers are localized within grains and, therefore, transport of charge carriers is likely to be dominated by the variable-range hopping (VRH) mechanism. In this case, the conductivity is generally in the form
In TiO2thin films, the charge carriers are localized within grains and, therefore, transport of charge carriers is likely to be dominated by the variable-range hopping (VRH) mechanism. In this case, the conductivity is generally in the form