Monodispersed CdSe Nanorods nanoprticles with sufficient luminescence intensity have been prepared by chemical method in solution phase. CdSe as a core covered by Olic acide as an organic capping agent. The nanodots size obtained by two methods: dir
ectly from high resolution transmission electron microscopy (TEM) and using absorption peaks comparison with literature, the two methods are in good agreement. The optical properties and the luminescence intensity as a function of CdSe NRs concentration and the type of solvent (Chloroform and Toluene) have been investigated. The intensity of photoluminescence peak decreases and the peak shifts toward the blue energy side as the concentration reduced. The results show the relation between the polarity, the effect of surface, concentration, and the quantum effect on the optical properties.
Monodispersed CdSe nanoparticles with sufficient luminescence intensity have been prepared by chemical method in solution phase, and in two forms: CdSe as a core covered by Olic acide as an organic capping agent, while the second form is CdSe as a co
re covered by a layer of CdS (CdSe/CdS core shell). The nanodots size obtained directly from high resolution transmission electron microscopy (TEM) and absorption peaks using Paul Mulvaneys formula are in good agreement. The optical properties and the luminescence intensity as a function of CdSe concentration and the type of solvent have been investigated. The intensity of photoluminescence peak decreases and the peak shifts toward the blue energy side as the concentration reduced
CdTe Thin films were deposited on glass substrates by thermal evaporation
method. The geometric thickness was calculated using interferometric method
based on reflectance curve recorded with the spectrophotometer. The XRD
analysis and optical char
acterizations of CdTe films with different optical
thicknesses reveals that the structure of the films is polycrystalline with
preferential orientation (111). The structure constant (a), crystallite size (D),
dislocation density (δ) and strain (ε) were calculated, and it is observed that the
crystallite size increases but micro-strain and dislocation density decreases with
increases in thin film thickness. The overall absorbance has been increased with
the film thickness and the direct band gap was obtained. It decreases with the
increase in the thickness of the films.
