ISSN 0020-1685, Inorganic Materials, 2009, Vol. 45, No. 5, pp. 468–473. © Pleiades Publishing, Ltd., 2009. Original Russian Text © M.V. Radchenko, G.V. Lashkarev, V.I. Sichkovskyi, A.A. Arshakuni, S.P. Gubin, V.O. Yuhimchuk, V. Domuhovskii, T. Story, Yu.P. Piryatinskii, G.Yu. Yurkov, 2009, published in Neorganicheskie Materialy, 2009, Vol. 45, No. 5, pp. 522–527. 468 INTRODUCTION During the last decade, the structural, optical, and electron properties of semiconductor nanostructures, including nanoparticles, have been intensively investi- gated, which is due to both fundamental interest and the possibility of their practical application. In particular, considerable study is being given to nanoparticles (quan- tum dots (QDs) based on CdS, CdSe, and CdS x Se 1 – x semiconductors in borosilicate and SiO 2 matrices. Such QDs are widely used in optoelectronics, laser technology, and biophysical investigations owing to manifestation of the unique optical properties caused by the effects of exci- ton space confinement [1, 2]. Moreover, the peculiarity of QDs consists in a very big surface-to-volume ratio. This leads to the sharpening of QD spectral characteristics and properties of surface atoms and ions, which can lead to surface polarization and an increase in the amount of sur- face states. The goal of present work is the investigation of structural and optical properties of nanoparticles of CdS composition formed in a polyethylene matrix. EXPERIMENTAL The cadmium sulfide nanoparticles stabilized in the bulk of a high-pressure polyethylene matrix were pre- pared according to the modified procedure of poly- meric matrix nanometallization [3]. The synthesis of the obtained nanoparticles can be conditionally divided into two stages. In the first stage, the addition of a cadmium chloride solution to the poly- ethylene + oil solution melt leads to the formation of CdCl 2 nanoparticles. The second stage consists in the interaction of the cadmium chloride nanoparticles with hydrogen sulfide which is bubbled through the polyethyl- ene + oil solution melt during the process of synthesis. The synthesis of CdS nanoparticles was performed in an argon flow at 260°ë and rate of solution melt stir- ring of 1200 rpm. The argon flow rate was adjusted in such a manner that provided a rapid and complete removal of the gaseous products of the reaction from the reaction vessel. After cooling to room temperature, the resulting waxlike reaction mixture was placed into a Soxhlet apparatus to extract the oil from the synthe- sized nanomaterial. The extraction of oil with benzene was performed for 10 h. The samples of polymeric nanocomposites contained 20 wt % CdS nanoparticles in the polyethylene with an average size of 4.9, 5.4, and 6.2 nm. The sizes of nanoparticles were changed by varying the concentration of the introduced calcium chloride solution. Nanomaterials Based on CdS Nanoparticles in Polyethylene Matrix M. V. Radchenko a , G. V. Lashkarev a , V. I. Sichkovskyi a , A. A. Arshakuni b , S. P. Gubin b , V. O. Yuhymchuk c , V. Domukhovski d , T. Story d , Yu. P. Piryatinskii e , and G. Yu. Yurkov f a Frantsevich Institute for Problems of Materials Science of National Academy of Sciences of Ukraine, Kiev, Ukraine b Kurnakov Institute of General and Inorganic Chemistry of Russian Academy of Sciences, Moscow, Russia c Lashkarev Institute of Semiconductor Physics of National Academy of Sciences of Ukraine, Kiev, Ukraine d Institute of Physics of Polish Academy of Sciences, Warsaw, Poland e Institute of Physics of National Academy of Sciences of Ukraine, Kiev, Ukraine f Institute of Metallurgy and Materials Science, Russian Academy of Sciences, Moscow, Russia e-mail: gy_yurkov@mail.ru Received February 14, 2007 Abstract—The synthesis of CdS nanoparticles stabilized in the bulk of a polyethylene matrix is described. The size of synthesized nanoparticles is determined by means of transmission electron microscopy. The composi- tion of nanoparticles is defined by X-ray phase analysis. It is shown that the variation of the process-dependent parameters during synthesis of nanoparticles in a polymer + oil solution melt results in the formation of CdS nanoparticles with average sizes of 4.9, 5.4, and 6.2 nm with a reasonably narrow size distribution and well- formed structure. The optical properties of synthesized nanomaterials are investigated. The investigation of Raman scattering reveals softening of the LO-phonon mode with decreasing CdS nanoparticle size. A broad high-energy band of photoluminescence connected with the exciton annihilation in conditions of size quantiza- tion is detected. DOI: 10.1134/S0020168509050021