Publications

Here we report the fabrication of a ZnO/SnO2 heterojunction on glass substrate using environment-friendly low cost-effective sol–gel drop coating method for UV assisted ethanol sensing. Surface, structural and elemental properties of the ZnO, SnO2 and ZnO/SnO2 thin film heterojunction was analysed by using Scanning electron microscope, EDX and X-ray diffraction (XRD) method that were confirming the polycrystalline nature of SnO2, ZnO, and their nanostructure thin film heterojunction. The electrical and gas sensing properties of SnO2, ZnO, and ZnO/SnO2 nanostructure thin film heterojunction was studied by fabricating metal (Ti/Al)-semiconductor (ZnO/SnO2)-metal (Ti/Al) structure exposed with different low concentration of the ethanol. An UV light exposure was carried out to improve the sensitivity towards ethanol of this heterojunction. Finally, density functional theory with Hubbard correction is employed to explore the band gap of the individual semiconductor monolayer and nanostructured ZnO thin film. The sensing properties of the heterojunction are revealed by density functional theory by exposing the ethanol molecule on the surface of the ZnO/SnO2.