Original scientific paper
Physical properties of nanoparticle silica gel doped with CdS prepared by sol-gel technique
I. K. Battisha
; Solid State Physics Department, National Research Center, Cairo, Egypt
Abstract
CdS/silica xerogel glasses were prepared via silica gels containing mixture solution of 0.2 M (CdCl2 and thiourea) with molar ratio 1:1. Doping the gels with this mixture solution and its heat treatment gave transparent yellow silica-gel glasses doped with CdS crystals. X-ray diffraction and transmission electron microscope make it possible to evaluate the nanoparticle size of the prepared samples. The nanoparticle size was dependent on the concentration of the dopant materials and the heating temperature. In the optical transmission spectra, the absorption edge exhibited a blue shift compared to that of the bulk CdS, and its energy shift was reciprocally proportional to the square of the radius. Thus the quantum-size effect could be found for the silica gel containing CdS prepared by the sol-gel process. The energy band gap shifted to higher energy for smaller nanoparticle size.
Keywords
CdS/silica xerogel; doping with CdCl2:thiourea mixture solution; XRD; TEM; TGA; DTA; FTIR investigations; nanoparticles; band gap energy
Hrčak ID:
301573
URI
Publication date:
1.5.2002.
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