Solvothermally synthesized europium-doped CdS nanorods: Applications as phosphors

Abstract

To exploit the photoluminescent behavior of CdSatnanoscalewith differentdopingconcentration of europium—a rare earth element, we report the synthesis of Eu-doped CdS nanorods by using low temperature solvothermal process by using ethylenedi amine. The outcomes can have future applications as phosphors, photovoltaic cells, lasers, light emitting diodes, bio-imaging, and sensors. The doping was confirmed by electron dispersive spectroscopy sup ported by X-ray diffraction. From scanning electron microscopy and transmission electron microscopy analysis it was observed that the average diameter of the Cd1-xEuxS nanorods is about 10–12 nm having lengths in the range of 50–100 nm. UV–Visible spec troscopy study was carried out to determine the band gap of the nanorods and the absorbance peaks showed blue shift with respect to the bulk CdS. The blue shift was also observed as the doping concentration of Eu increases. From photoluminescence (PL) studies at kex = 450 nm,peaksat528and540 nmwereobserved due to CdS, peak at 570 nm is due to defects related transitions, while the peak at 613 nm is due to Eu. As the dopingconcentration of Eu is increasedthe intensity of the luminescent peak at 613 nm is increased. Thermogravimetric analysis showed the nanorods are thermally stable up to 300 C. The traces of impurities adsorbed on the nanorods were confirmed by Fourier transform infrared spectroscopy.