Detection of Methanol by a Sensor Based on Rare-earth Doped TiO₂ Nanoparticles

Abstract

The rare earth doped TiO₂ was prepared and characterized with Nd, Ho and Y as the doping agents, which have obvious absorption in visible light area. The particle size of the glomeration was about 200–400 nm. TiO₂ sensor performed a significant change in resistance when exposed to methanol vapor. By comparison, the Nd, Ho and Yb doped TiO₂ sensors exhibited a response of 2.22, 4.05 and 3.78, and lowered response and recovery times of 91, 56 and 67 s, respectively. The Ho doped TiO₂ showed the best methanol-sensing properties, which exhibited high selectivity and response to methanol compared with the other tested vapors. In concentration of 0–10 ppm, the sensor exhibited excellent stability for detecting methanol at various concentrations.

Keywords

rare earth / TiO₂ / sensor / methanol / stability

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