Electronic conduction properties of TiO2 thin films under UV light irradiation

Abstract

TiO2 has photocatalysis. When UV light is irradiated, electron-hole pairs are generated in TiO2. The source of photocatalysis is oxidation and reduction reactions at the surface due to electrons and holes. Therefore, it is considered that the photocatalytic activities are closely related to electronic properties of the TiO2 under UV light irradiation. In this paper, we obtained Hall voltage properties in anatase TiO2 thin films under UV light irradiation. Furthermore, we successfully separated two current components due to electrons and holes using a new technique. We obtained the following results; 1. The measured values and polarity of the Hall voltage were not stable compared with those of n-type silicon. 2. The current component of electrons was almost the same with that of holes. From these results, it is suggested that the values of electron mobility and hole mobility are close.