Monitoring of UV-A radiation by TiO2/CdS nanohybrid along with the high on-off ratio

Abstract

Exposure to UV-A light can have detrimental effects on human health, leading to skin damage and an increased risk of skin cancer. In this study, we employed a hydrothermal-assisted method to cultivate TiO2-decorated CdS nanorods for use in UV photodetectors. Our research culminated in the fabrication of an exceptionally responsive and rapid photodetector based on the TiO2/CdS nanohybrid. X-ray diffraction analysis revealed the hexagonal phase of CdS nanorods, predominantly oriented along the (002) plane, and the presence of the anatase phase of TiO2. Scanning electron microscopy (SEM) measurements confirmed the nanorod structure of TiO2/CdS. Optical properties of the TiO2/CdS nanohybrid were investigated through UV–visible absorbance analysis. Additionally, X-ray photoelectron spectroscopy (XPS) provided insights into the surface composition of the prepared nanohybrid, with peaks corresponding to Cd 3d3/2 and Cd 3d5/2 at binding energies of 411.47 eV and 404.73 eV, respectively, and confirming the presence of titanium through peaks of Ti 2p3/2 and 2p1/2 at binding energies of 458.31 eV and 463.8 eV, respectively. Raman analysis indicated the presence of the anatase phase of TiO2 in the composite. Our device exhibited an impressive detectivity of 9.9 × 1012 Jones, an EQE (external quantum efficiency) of 971.36%, and a high photoresponsivity of 2.86 A/W. These results suggest that TiO2/CdS nanohybrids, prepared using a cost-effective and straightforward method, hold promise for UV photodetection applications.