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Crystal growth in the surface of selenium bulk samples and in selenium thin films of different thicknesses has been studied under isothermal conditions using different microscopy techniques (optical, infrared, and scanning electron microscopy). The structure of the formed crystals is described with respect to previous publications focused on crystal growth in selenium thin films and bulk samples. Crystal growth rates were obtained from the linear dependence of crystal sizes on annealing time. Such behavior assumes that crystal growth is driven by liquid–crystal interface kinetics. The crystal growth rates found in the surface of bulk samples are comparable with those found in thin films and a few orders of magnitude higher than previously published growth rates of volume crystals formed in selenium undercooled melts. The crystal growth rates were scaled with the viscosities to analyze the Stokes–Einstein relation. A relatively high decoupling between the crystal growth rate and viscosity occurs in the studied samples of amorphous selenium. Therefore, the standard screw dislocation growth model is corrected for the decoupling, which provides a satisfactory description of the crystal growth rate over a wide temperature range.

Anodic self‐organized TiO2 nanotube layers (with different aspect ratios) were electrochemically infilled with CuInSe2 nanocrystals with the aim to prepare heterostructures with a photoelectrochemical response in the visible light. The resulting heterostructure assembly was confirmed by field‐emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X‐ray diffraction (XRD). High incident photon‐to‐electron conversion efficiency values exceeding 55% were obtained in the visible‐light region. The resulting heterostructures show promise as a candidate for solid‐state solar cells.

Crystal growth, viscosity, and melting were studied in Ge2Sb2Se5 bulk samples. The crystals formed a compact layer on the surface of the sample and then continued to grow from the surface to the central part of the sample. The formed crystalline layer grew linearly with time, which suggests that the crystal growth is controlled by liquid-crystal interface kinetics. Combining the growth data with the measured viscosities and melting data, crystal growth could be described on the basis of standard crystal growth models. The screw dislocation growth model seems to be operative in describing the temperature dependence of the crystal growth rate in the studied material in a wide temperature range. A detailed discussion on the relation between the kinetic coefficient of crystal growth and viscosity (ukin ∝ η(-ξ)) is presented. The activation energy of crystal growth was found to be higher than the activation energy of crystallization obtained from differential scanning calorimetry, which covers the whole nucleation-growth process. This difference is considered and explained under the experimental conditions.

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The presented study shows how the incorporation of silver changes the structure and physical properties of chalcogenide glass (GeS2)50(Sb2S3)50. Nine samples with silver content (0-25 at. %) were studied to give a detailed picture. The structure and its changes were analyzed by Raman spectroscopy. The main structural units of the (GeS2)50(Sb2S3)50 glass and its medium range order were described. Interaction of silver and hosting (GeS2)50(Sb2S3)50 matrix was described by a set of chemical reactions. The weakest part of the hosting matrix, two interconnected SbS3/2 pyramids, was identified. Such structural motif was identified as the doorway for silver incorporation. The material hardness is significantly increased by up to 26% due to silver addition. The ability of silver to fill cavities in a glass is responsible for the observed hardness increase. Electronic properties and silver ion mobility were examined by impedance spectroscopy and radioactive tracer diffusion. The purpose of the presented study is to give an instructive description of how silver change the structure of the studied chalcogenide glass and give a complex feeling of how the silver changes its physical properties.