A novel microwave synthesis of nanocrystalline SnO_2 and its structural optical and dielectric properties

摘要

Nanocrystalline SnO_2 particles with the rutile structure have been successfully synthesized by a novel microwave irradiation method. This process requires less reaction time and low temperature. Transmission electron microscopy studies show that SnO_2 particles are in spherical shape with size about 25-30 nm. Selected area electron diffraction pattern confirms single crystalline nature of the SnO_2. UV-Vis spectrometer was carried out to study the optical properties and estimated band gap energy of SnO_2 particles is 3.55 eV. In Fourier transform infrared study, a defined peak at around 615 cm~(-1) is observed due to Sn-O vibration. Frequency dependent dielectric anomaly is observed in SnO_2 nanoparticles at low temperature. It is found that the value of dielectric constant of SnO_2 particles at 10 kHz is found to be 777.5. It systematically decreases with increasing frequency whereas increases with increasing temperature. Further, the prepared samples were characterized by Photoluminescence spectroscopy and energy dispersive spectroscopy.