Optical, morphological, electrical properties of ZnO-TiO2-SnO2/CeO2 semiconducting ternary nanocomposite

Abstract

Low dielectric constant and low dielectric loss with moderate wide bandgap, novel semiconducting metal oxide composites are useful materials for applying optoelectronic, microwave dielectric ceramics. A less dielectric constant is required for wireless communication to reduce the cross pairing between conductors and also for fast signal transmission. In the present study, the structural, optical, and dielectric properties of ternary ZnO - TiO2 added with SnO2/CeO2 semiconducting nanocomposite materials were investigated and synthesized by the solid-state gelation method. The samples were sintered at a temperature of 450 0C. The X-ray diffraction patterns of composites revealed the existence of TiO2 anatase phase, SnO2, and CeO2. The average crystallite size at d101 was measured using the Scherer method, ranging from 6.18 nm to 9.13 nm. The overall crystallite size was calculated using the Size-strain plot method, and it is in the range of 14.8 nm to 17.16 nm. The surface morphology of all samples appears uniform in size and spherical shape. The average particle size of grains was 35 nm. The absorbance properties studied by UV–Visible spectroscopy and bandwidth were 2.6 eV calculated using Tauc’s plot method, and it reveals the formation of new energy levels. The dielectric properties of pellet dimensions of 1 mm thickness and 10 mm diameter, measured from the LCR meter, are indicated at 1 kHz frequency. The most significant dielectric constant (εr) and lowest loss tangent (Tan δ) are 53.89 and 0.25 for pure ZnO - TiO2, and the lowest dielectric constant (εr) and less loss tangent (Tan δ) are 9.69 and 0.38 for 1 wt% CeO2 doped to ZnO - TiO2. The conductivity of the composite is in the range of 10-7 S/cm. With additive concentration to ZnO - TiO2, both SnO2 and CeO2 are equally potential and modifies the parameters due to the similar bandgaps and more oxygen availability.