Synthesis of ZnO and CuO–ZnO nanocomposites for photo-conducting and dielectric applications

Abstract

Zinc oxide (ZnO) and its composites has garnered a tremendous attention lately due to its effective role in electronic and optoelectronic applications. The present manuscript reports the synthesis and characterization of ZnO and CuO–ZnO nanocomposites. These samples were synthesized using precipitation technique and studied for voltage-dependent dielectrics and photoconductivity properties. Structural properties were thoroughly investigated using powder X-ray diffraction (PXRD) measurements. The composite material revealed decreased crystallinity and increased strain in the material. Optical absorption measurements were recorded using UV–vis diffusion reflectance measurements and the changes in the absorbance spectrum corresponding bandgap is explored. The obtained band gap is comparatively less for the composite material when compared with prestine ZnO. Structural morphology of the synthesized materials was observed and compared and changes in the composites when compared with the ZnO. Drastic changes in the morphology is witnessed. Electrical response of these synthesized semiconductors was studied using I–V and dielectric measurements. CuO–ZnO samples show a very clear sensitivity to the voltage dependent dielectric properties compared to ZnO. The composite and ZnO are studied using I–V measurements and the light dependent I–V measurements and composite revealed photo sensitivity. Drastic change in the conductivity is witnessed inferring the material to be used in optoelectronic application. Dielectric, Impedance, dielectric loss, AC conductivity and modulus index of the materials were explored by subjecting the materials to impedance measurements. The materials were also explored with different voltages and compared. The composite material revealed drastic variations for change in the voltage and measured parameters were compared with the ZnO.