Optical and structural properties of SnO2:Sb gels and thin solid films prepared by dip-coating method

摘要

Sb doped and undoped SnO$-2$/ thin solid coatings were prepared by the dip-coating technique via the sol-gel route using a SnCl$- 4$/ precursor. Aqueous gels of undoped compound were made according to Hiratsuka and doping was achieved through the addition of SbCl$-3$/ in the concentration range of 1 - 10 mol%. FT-IR spectroscopy was utilized to determine the influence of Sb dopant on the vibrational modes of oxohydroxo skeleton of the gel. It was found that oxo bridges between Sb dopants and tinoxohydroxo polymeric species were favored in doped gels. Doping brings about a broadening of the x-ray diffraction peaks and increases the infrared reflectivity of the samples (approximately 50%) in the spectral range 4000 - 600 cm$+$MIN@1$/, due to the formation of the plasma mode. The dip- coating process gives 0.03 - 0.10 $mu@m thick films per dipping, depending on the viscosity of the gel and the dopant concentration. The lowest electrical resistivity of the doped SnO$-2$/ coating is 1.2.10$+$MIN@2$/ approximately ega cm and is comparable to the electrical resistivity of the alkoxide derived Sb doped SnO$-2$/$+2$/.