Greener synthesis and characterization of cadmium-tellurium quantum dots using aqueous extract of waste orange peel

Abstract

Cadmium-Tellurium quantum dots are inorganic semiconductor material. In the present study, highly stable Cadmium-Tellurium (CdTe) quantum dots with good optical properties were successfully synthesized by using waste orange peel extract. Fourier-transform infrared spectroscopy (FTIR) identified the presence of hydroxyl, carboxyl and amine groups. Multifunctional X-ray Photoelectron Spectroscopy (XPS) confirmed the presence of cadmium and tellurium. The average size of the quantum dots was found to be 6nm using Transmission Electron Microscopy (TEM). The cubic zinc blende type crystalline structure of quantum dots was confirmed by X-ray powder diffraction (XRD). Thermal stability was studied using thermo-gravimetric analysis (TGA). The influence of temperature with respect to mass change of 8% was observed at 200°C. The high luminescence property exhibits at the wavelength of 502 nm were investigated using photoluminescence analysis (PL) and the blue shift is confirmed by UV-Visible spectroscopy.