Synthesis and optical properties of Eu3+ doped CdS nanostructures

Full text: Semiconductor nanoparticles doped with rare earth (RE) ions have been intensively investigated because of their potential applications in optoelectronics, fibre amplifiers and solid-state lasers. In the present investigation effect of europium ion on the optical properties of the nanocrystalline CdS have been studied. Eu3+ doped cadmium sulphide (Cd0.98Eu0.2S) nanocrystals were synthesised by coprecipitation method using isopropyl alcohol (IPA): DI water and ethylene glycol (EG): DI water as mixed solvents. Powder X-ray diffraction reveals the formation of hexagonal (wurtzite) phase of Eu3+: CdS. The average size of the particle was calculated to be 3.65 nm using Scherrer equation with broad (002) peak. From the SEM micrographs it is clearly observed the formation of flower, stars and paddy like structures of Eu3+: CdS for different mixed solvents. The chemical homogeneity of the samples was confirmed using EDX analysis. Band gap values of Eu3+: CdS synthesized from different solvents were estimated using UV-reflectance spectra. The crystallite size calculated from the band gap values was well agreed with the diffraction data. The presence of Eu3+ on the surface of nanoparticle significantly increases the emission intensity of the CdS, similar results were observed by Ageeth et al. The shift in the emission and efficiency of Eu3+: CdS depends on size and shapes of the synthesised nanoparticles