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The surface polymerization of aniline producing polyaniline nanofilms on surfaces in contact with the reaction mixture has been investigated. The hypothesis that aniline polymerization is heterogeneously catalyzed by the surfaces has been tested. This concept is applicable to planar surfaces and also to surfaces provided by microparticles. The introduction of silica gel, a substrate with a large specific surface area, led to the acceleration of polyaniline formation. The effect of silica gel concentration, particle size, and porosity is discussed, and the courses of polymerization in the presence of porous and compact spheres are compared. It can be concluded that the initiation of aniline polymerization is promoted by adsorption of oligomeric intermediates at the surface. The surface polymerization, giving rise to polyaniline coatings, is thus preferred to precipitation polymerization in the aqueous phase that produces a polyaniline precipitate. The coating of the silica gel surface with polyaniline was not complete, as demonstrated by X-ray photoelectron spectroscopy. The infrared spectrum of the polyaniline coating on silica gel has been compared with that of the PANI film deposited on silicon.

Based on the results obtained for C–N and Si–C–N films, a systematic investigation of reactive magnetron sputtering of hard quaternary Si–B–C–N materials has been carried out. The Si–B–C–N films were deposited on p-type Si(100) substrates by dc magnetron co-sputtering using a single C–Si–B target (at a fixed 20% boron fraction in the target erosion area) in nitrogen-argon gas mixtures. Elemental compositions of the films, their surface bonding structure and mechanical properties, together with their oxidation resistance in air, were controlled by the Si fraction (5–75%) in the magnetron target erosion area, the Ar fraction (0–75%) in the gas mixture, the rf induced negative substrate bias voltage (from a floating potential to −500V) and the substrate temperature (180–350°C). The total pressure and the discharge current on the magnetron target were held constant at 0.5Pa and 1A, respectively. The energy and flux of ions bombarding the growing films were determined on the basis of the discharge characteristics measured for the rf discharge dominating in the deposition zone. Mass spectroscopy was used to show composition of the total ion fluxes onto the substrate and to explain differences between sputtering of carbon, silicon and boron from a composed target in nitrogen-argon discharges. The films, typically 1.0–2.4μm thick, possessing a density around 2.4gcm−3, were found to be amorphous in nanostructure with a very smooth surface (Ra⩽0.8nm) and good adhesion to substrates at a low compressive stress (1.0–1.6GPa). They exhibited high hardness (up to 47GPa) and elastic recovery (up to 88%), and extremely high oxidation resistance in air at elevated temperatures (up to a 1350°C substrate limit).

Nanocrystalline diamond thin films are grown on silicon and glass substrates by microwave plasma (MP)CVD from a gas mixture of methane and hydrogen at low substrate temperatures. The initial stages of diamond growth, i.e., i) the growth of individual nanometer-sized crystals and clusters, and ii) coalescence into a continuous layer, are investigated by diverse analytic techniques. Atomic force microscopy (AFM) measurements reveal nearly unchanging surface roughness up to 40 min. X-ray photoelectron spectroscopy (XPS) measurements detect changing of the surface composition from the very beginning of the growth process. The rapid carbon increase is assigned to the enlarging of the grown crystals and clusters. Scanning electron microscopy (SEM) images indicate a possible lateral growth type. The found dependences indicate that a two-dimensional growth mode takes place at low substrate temperatures. Grown nanocrystalline diamond films are optically transparent in a wide spectral range, and exhibit a high refractive index of 2.34.

Composite polyaniline−silica films produced on glass surfaces during the dispersion polymerization of aniline in the presence of colloidal silica were investigated. The film morphology and composition were characterized by FTIR, UV−vis, and X-ray photoelectron spectroscopies. Compared with pure polyaniline films produced under similar conditions, the composite films are thinner and smoother, and their surface is silica rich. The film thickness of both pure and composite films decreased as the polymerization temperature increased from 0 to 50 °C. To determine the particle size of polyaniline-silica dispersion particles, which are formed at the same time as the films, dynamic light scattering was used. The correlation between the particle size and film thickness is discussed. The electrical conductivity of composite polyaniline films was only a little affected by the presence of silica.