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The photoluminescent properties of CdS clusters of different size in porous glasses

Rysiakiewicz-Pasek E., Polańska J., Gevelyuk S.A., Doycho I.K., Mak V.T., Zhukov S.A.

Optica Applicata

2008

Vol. 38, nr 1

93-100

CdS nanoclusters were formed in the porous glass matrix by sequential chemical deposition from liquid-vapor phase and their chemical content was investigated. The room temperature photoluminescence spectra of specimens excited with a 235 nm wavelength had typical narrow peaks at 400 nm. The peaks can be explained by quantum effects for charge carriers confined inside the small-size (radius of the order of several nanometers) clusters. At the same time the luminescence spectra of the same specimens, but excited with a xenon lamp at 77 K, had peaks at ~700 nm that approximately corresponded to the band gap of the crystalline CdS. The possibility of the crystallites existence follows from the size distribution of voids in the porous glass matrix and is confirmed by the X-ray spectra typical of the wurtzite structure. The peculiarities of the observed luminescence spectra are explained by the energetic diagram of CdS in the configurational space.

Influence of gamma -irradiation on the photoluminescent properties of porous glasses.

Gevelyuk S.A., Lishchuk D.E., Mak V.T., Rysiakiewicz-Pasek E., Marczuk K.

Optica Applicata

2000

Vol. 30, nr 4

595-603

The influence of small doses of gamma -irradiation on the features of the photoluminescence spectra of porous silica glass during long-time (several months) storage after the irradiation is investigated. The non-monotonic dependence of photoluminescence change on the dose of the glasses with a different composition and different additional pre-treatment is observed. The analysis of intensity changes and shifts of the maxims of the photoluminescence spectra shows long-time oscillations. This indicates that the composite catalytic processes take place on the surface of the pores. Perhaps the small gamma -radiation doses initiate the cyclic process of the surface state transformation on the inner side of the pores.