Room temperature acetone sensing performance of Pt/Sb2O3 impregnated Fe2O3 thin film: Noninvasive diabetes detection.

• Room temperature ppm level acetone sensing by Pt/Sb 2 O 3 impregnated Fe 2 O 3 thin film. • ~6 µm films were drop casted on planar alumina substrates with platinum electrodes. • Enhanced sensing response ~2.4 with ~95 s recovery time observed for 1 ppm acetone. • Even at 0.25 ppm acetone vapour, the response observed ~1.4. • Real time breath acetone measurement was also carried out. • The sensor revealed reproducible performance over a period of about two months. In the present report, an enhanced sub-ppm level acetone sensing performance of a novel Pt and Sb 2 O 3 impregnated nanocrystalline Fe 2 O 3 thin film operating at room temperature has been explored. Starting from organic precursor sols, thin films of thickness ~ 6 µm were drop-casted on planar alumina substrates pre-attached with the platinum electrodes and cured at ~ 350°C. The characterizations of the materials have been carried out using X-ray Diffraction, FTIR, Raman Spectroscopy, micro structural study through FESEM and TEM as well as XPS analyses. The sensing characteristics including sensing response, lowest detection limit, recovery time etc. of these chemiresistive thin films were studied on exposing them to various concentrations (0.25 to 1 ppm) of acetone at room temperature. The sensing response of ~2.4 with ~ 95 s recovery time was observed on exposure to 1 ppm acetone for 10 s. Even at 0.25 ppm acetone, the response observed ~ 1.4. Selectivity study on different alcohols and other interfering gases of breath has also been tested. Additionally, a real time breath acetone measurement was carried out and acetone sensing mechanism has been elucidated. [ABSTRACT FROM AUTHOR]