A Water Vapor Sensor Application of Sn_(1-x)Fe_xO_(2-δ) Fibers

摘要

Tin oxide is of great interest due to their potential technological applications, such as: gas sensors, energy conversion, catalysts and others. Appropriate doping can further enhance the conductivity of the SnO_2 material with little loss of transparency. Isolated tin iron oxide fibers (Sn_(1-x)Fe_xO_(2-δ)) with x (molar%) = 0, 2, 4, 6, 8 and 10 were prepared by the electrospinning technique. Anhydrous SnCl_4, FeCl_3.6H_2O, different alcohols, chloroform and a polymer (PEO) were used as precursor materials. Appropriate mixture of these reagents defines the deposition solution. The samples were deposited on glass substrates and annealed at 500°C. The fibers are characterized by scanning electron microscopy (SEM), impedance spectroscopy and temperature dependence current-voltage measurements. The fibers with diameters between 2 to 12 microns were used for sensorial purpose. Thus, water vapor sensor responses were also measured and the experimental results are tested using the Freundlich isotherms model.