CeO 2 thin film as a low-temperature formaldehyde sensor in mixed vapour environment

Nanostructured cerium oxide thin film was deposited onto the glass substrate under optimized condition using spray-pyrolysis technique. X-ray diffraction result indicates polycrystalline nature of the film with fluorite-type face-centered-cubic structure. The atomic force micrograph indicates the presence of nanocrystallites over the film surface. The vapour sensing characteristics of the annealed film were studied by chemiresistive method for various concentrations of formaldehyde vapour at room temperature (~ 30 °C). For 0.5 ppm of formaldehyde vapour, the film shows a response and recovery time of 36 and 1 s, respectively. The vapour sensing properties of the cerium oxide film in mixed environment were studied and reported.