Synthesis and Humidity Sensing Properties of Sn-Doped Nano-TiO2

Abstract

Nanostructured Sn-doped TiO2have been prepared by ball milling using SnO2and TiO2as raw materials. The as-prepared powders are characterized by XRD, SEMs and EDAX to identify the structural phases, surface morphology, and composition of the materials. The materials are prepared with the addition of tin of different molar ratios (0, 0.05, 0.10, 0.15, 0.20, 0.25, and 1.0) to TiO2and sintered at 800°C for 3 h. They are subjected to dc resistance measurements as a function of relative humidity (RH) in the range of 30%–97% in a self-designed humidity chamber, and the results revealed that the sensitivity factor increased with an increase in tin molar ratio. Among them, TiO2—20 wt% of SnO2possessed the highest humidity sensitivity, while the pure TiO2and SnO2composite possessed a low sensitivity.