Structural, Optical, Electrical, and Photoresponse Properties of Postannealed Sn-Doped ZnO Nanorods

Abstract

Tin (Sn) doped ZnO nanorods were synthesized on glass substrate using a sol-gel method. The synthesized nanorods were postannealed at 150, 350, and 500∘ C. The surface morphologies of Sn-doped ZnO nanorods at different postannealing temperatures were studied using scanning electron microscope (SEM). XRD results show that as the postannealing temperature increased from 150∘C to 500∘C, the c-axis orientation becomes stronger. Refractive indices and dielectric constants were calculated on the basis ofdifferent relationships by utilizing bandgap values. These bandgap values were obtained in terms of optical absorption by using a UV-Visible spectrophotometer. The enhancing effects of annealing temperatures on electrical properties were observed in terms of current-to-voltage measurements. Resistivity decreases as postannealing temperature increases from 150∘C to 500∘C. Annealed samples were evaluated for UV-sensing application. The samples exhibit a responsivity of 1.7 A/W