Screen printed In₂O₃-SnO₂ nanocomposite: Structural and morphological properties and application for NO₂ detection

I. Madhi^a, M. Saadoun and B. Bessaïs

Laboratoire de Photovoltaïque, Centre de Recherche et des Technologies de l’Energie, Technopole de Borj-Cédria, BP 95, 2050 Hammam Lif, Tunisie

^a e-mail: i.madhi@yahoo.fr

Published online: 18 June 2012

Abstract

In this work, we report on the sensing properties of screen-printed In₂O₃ (Indium Oxide) while adding a moderate quantity of SnO₂. It was found that the addition of SnO₂ improves the response and decreases the operating temperature of the sensitive element for NO₂ detection. However, a non-controlled amount of SnO₂ leads to opposite result; for this reason in the present investigation we test films with different composition in order to optimize the quantity of SnO₂ to be added. The crystallinity, roughness and morphology of the obtained In₂O₃-SnO₂ anocomposite were analyzed using X-ray Diffraction (XRD), Transmission Electronic Microscopy (TEM) and Atomic Force Microscopy (AFM). The atomic composition of the In₂O₃-SnO₂ films was determined with the energy dispersive spectroscopy (EDX) analysis during TEM observations. The effect of the composition on the cristallinity and morphological properties of the films was analyzed. Finally, the In₂O₃-SnO₂ films were tested like sensitive elements for NO₂ detection, wherein the effect of the composition was correlated with the sensor response in NO₂ ambient. It was found that the addition of a moderate quantity of SnO₂ to In₂O₃ exhibited high sensitivity at rather lower operating temperatures.