A novel microwave synthesis of nanocrystalline SnO₂ and its structural optical and dielectric properties

Nanocrystalline SnO₂ 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 SnO₂ particles are in spherical shape with size about 25–30 nm. Selected area electron diffraction pattern confirms single crystalline nature of the SnO₂. UV–Vis spectrometer was carried out to study the optical properties and estimated band gap energy of SnO₂ 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 SnO₂ nanoparticles at low temperature. It is found that the value of dielectric constant of SnO₂ 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.