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High-grade zeolite nanocomposites are synthesized utilizing solid by-products from combustion of coal for energy production in Thermal Power Plants applying alkaline aging, hydrothermal and fusion-hydrothermal activation procedures. The obtained coal ash zeolites were studied with respect to their chemical and phase composition, morphology, surface parameters and thermal properties. It was found that they are distinguished in nanocrystalline morphology and significant content of iron oxide nanoparticles (γ-Fe2O3, α-Fe2O3, γ-Fe3O4) and doping elements (Cu, Co, Mn, V, W, etc.) transferred from the raw coal ash, and therefore they are assumed as nanocomposites. Coal fly ash zeolite nanocomposites are characterized by a mixed micro-mesoporous texture, significant concentration of acidic Brønsted centers due to their high surface insaturation, high chemical and thermal stabilty. This unique combination of compositional and textural properties predetermines the application of these materials as catalysts for thermal oxidation processes, anticorrosion barrier coatings, carbon capture adsorbents, matrices for hosting functional groups, detergents etc. Examples for coal fly ash zeolite applications for substitution of critical raw materials in practice are provided.

Films composed of Si, C, O and N have been deposited by low pressure chemical vapour deposition (LPCVD) from different chemical systems: pyrolysis of C 3 N 3 Cl 2 N(SiMe 3 ) 2 and interaction between SiCl 4 C 2 Cl 4 , NH 3 and H 2 O vapour. The composition, chemical bonding and structure of the films were investigated by a variety of analytical techniques. The physicochemical and electrical properties of the layers were also studied and it was found that films exhibit low static dielectric constants in the ranges of 2.8 - 3.5 and 1.7 - 2.5 for the two chemical systems, respectively. These low-k values combined with the high density, good adhesion and chemical inertness of the films, make them very attractive for future device technology application.

Thin carbon nitride films have been prepared by inductively coupled plasma chemical vapour deposition (ICP-CVD). Instead of using conventional gaseous carbon precursors, a pure carbon mesh was used as a carbon source with nitrogen as a transport gas The basic process parameters varied were the r.f. power (up to 100 W) and the pressure in the reactor. The films were composed of nitrogen and carbon as revealed by Auger electron spectroscopy (AES), X-ray excited photoelectron spectroscopy (XPS) and heavy ion elastic recoil detection (ERD) analysis, and their nitrogen fraction N/(N+C) was at about 0.5, independent on the experimental conditions. From Fourier transform infrared spectroscopy (FTIR) and XPS data it can be concluded that carbon atoms were bonded in different ways (by triple, double and single bonds) to nitrogen atoms.