Fabrication of thin-film WO3 sensors and their sensing properties to dilute NO2

摘要

We tried to fabricate WO3 thin-film sensors using four kinds of WO3 particles with very different crystalline morphologies (spherical, disk, cuboid, and hexagonal). Using highly dispersive suspensions prepared, WO3 thin films of 1.5–3.0 μm in mean thickness were obtained by micro-injecting film formation method. NO2 sensing properties of these thin-film sensors suggested that the sensitivity to NO2 as well as the rate of response-recovery depended markedly on morphology and microstructure of the WO3 crystals contained.