Effect of the Solvent Effect of the Solvent Used During the Preparation of SnO₂ Nanoparticulated Methane Sensor

Abstract

Gas monitoring is a relevant activity for industrial and domestic applications due to usage of dangerous gases as methane, which has been increasingly used as domestic and industrial fuel. In this field of research, metallic oxides such as SnO₂, ZnO and Fe₂O₃ have been widely studied, but we are far from reaching the total understanding of all the parameters that can be varied; in order to improve the gas sensing properties of the metallic oxides. In this work, we present the change of properties derived from using different solvents during the preparation of SnO₂ nanoparticles via the sol-gel process. The nanoparticles suspended in two different solvents were deposited on glass substrates by the dip-coating method. The addition of Sb as a dopant was studied at two different Sb:Sn ratios of 1:99 and 1:2. SEM showed differences in the nanostructured topology of the samples and EDS analysis was performed to determine the elemental composition of the samples and the ratios of doping. XRD spectroscopy was used to determine the phase of the materials and the crystallite size. Measurements of the electric response of the coatings to methane, under controlled conditions at different temperatures, were carried out and curves of sensitivity versus temperature were obtained.