Characterization of amorphous Pt/ZnO films grown on silicon(100) substrates by a photochemical metal organic deposition and their potential use as gas sensors

• Published in: Polyhedron 2013-10, Vol.62, p.1-6
• Main Authors: Buono-Core, G.E., Klahn, A.H., Cabello, G., Lillo, L.
• Format: Article
• Language: English
• Subjects: Carbon monoxide sensor; Photochemical deposition; Photoelectron spectroscopy; Thin films; Zinc oxide
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2013.06.028

Pt loaded zinc oxide thin films have been successfully prepared by direct UV irradiation of amorphous films of β-diketonate complexes on Si(100) substrates. Photodeposited films were characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Sensing capacities of the Pt/ZnO films towards carbon monoxide were evaluated. Pure and 10% Pt-loaded zinc oxide thin films have been successfully prepared by direct UV irradiation of bis(β-diketonate)zinc(II) and Pt(II) precursor complexes spin-coated on Si(100) substrates. The surface morphology of the films was characterized using atomic force microscopy (AFM) and it showed that the as-photodeposited films are amorphous and have a rougher surface than thermally treated films. The chemical composition of the films was determined by X-ray photoelectron spectroscopy (XPS). The results indicated the presence of ZnO and PtO on the surface of as-deposited loaded zinc oxide films. Gas sensing tests reveal that as-deposited 10% Pt/ZnO films exhibit a better response than pure ZnO films towards 20ppm carbon monoxide at an operating temperature of 250°C. The sensors also have fast response and recovery characteristics.