Synthesis and characterization of antimony doped tin oxide aerogel nanoparticles using a facile sol–gel method

High purity antimony doped tin oxide (ATO) aerogel nanoparticles with various concentrations of Sb have been successfully synthesized using modified sol–gel method. In this process, hydrolysis was slowly released and followed by a thermal drying in supercritical conditions of ethanol. The aim of this study is to enhance the properties of nanoparticles with low doping concentration and low cost. The structural, morphological, optical and electrical properties were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, UV–Vis–IR spectroscopy, Fourier transform infrared spectroscopy (FTIR) and impedance spectroscopy, respectively. We show that ATO aerogels have a polycrystalline tetragonal rutile structure with a highly (110) plane preferred orientation. The grain sizes are in the range of 13–23 nm, dependending on the elaboration conditions. Raman spectra reveals fundamental peaks at 483, 633, and 770 cm− 1, corresponding to the Eg, A1g and B2g vibration modes, respectively, in a good agreement with those for the rutile bulk SnO2. The optical band gap of tin oxide increases slightly from 3.88 to 3.94 eV with the increase of Sb content. Impedance spectroscopy results indicate that the electrical properties are strongly dependent on temperature and doping rate. All results suggested that the as-prepared ATO nanoparticles were good quality material for thin film solar cell applications.