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This work focuses on the fabrication of stoichiometric CuInSe 2 nanostructures with controllable physical parameters of the nanocrystals suitable for hybrid organic/inorganic photovoltaics. CuInSe 2 nanostructures were prepared by the chemical close-spaced vapor transport (CCSVT) method onto Mo/barrier/glass substrates by using an In 2 Se 3 source material and Cu precursors. The In 2 Se 3 source material was volatilized in H 2 ambience with the addition of HCl vapors at 550 °C. Three different types of Cu precursors were used: (i) Cu thin films (6–250 nm thick) deposited by e-beam, (ii) Cu nanoparticles prepared by spray pyrolysis and (iii) Cu nanostructures formed by applying the nanosphere lithography (using a monolayer of 450 nm nanospheres). The CCSVT process parameters were varied to reveal the optimum conditions for the preparation of secondary phases free CuInSe 2 nanostructures. The structural characterization by x-ray diffraction in both grazing incidence and Θ-2Θ configurations revealed the formation of CuInSe 2 chalcopyrite phase independently on the applied precursor type. The elemental composition of the as-prepared CuInSe 2 nanostructures was analyzed by laser ablation-inductively coupled plasma mass-spectrometry. In non-optimised processes, an excess of Se compared to stoichiometric composition was detected and attributed to the formation of molybdenum selenide and indium selenide phases. The formation of the latter secondary phases was suppressed by tuning the CCSVT deposition parameters. [ABSTRACT FROM AUTHOR]

The polymer/ As-Se-S-Te structure for X-ray imaging has been investigated. The possibility of registering relief-phase images for radiation of "white" spectrum and λ=0,154 nm of Cu anode X-ray tube was shown. [ABSTRACT FROM AUTHOR]

The polymer/67at %(As2S3)0,985(Bi2Se3)0,015:33 at.% As2Se3 structure for X-ray imaging has been investigated. The possibility of registering relief-phase images for radiation of "white" spectrum of tungsten anode X-ray tube was shown. [ABSTRACT FROM AUTHOR]

Abstract: The investigation of the charge carrier energy states in CdS/CdTe solar cells was based on the studies of absorption and photoconductivity spectral dependencies, quantum efficiency, photoconductivity kinetics measurements at 78 and 300 K. The analysis of the absorption spectra of cadmium telluride (CdTe) films used as a component of SnO2/CdS/CdTe/Ni solar cells, had shown that its heat treatment in CdCl2 leads to the formation of an impurity level localized at ∼20 meV from the top of CdTe valence band. The high photovoltaic properties of the SnO2/CdS/CdTe/Ni solar cells are determined by the presence of the recombination level with a lifetime equal to 180 μs. The heterojunctions heat treatment in CdCl2 leads to the structure defects removal in the semiconductor layers, recrystallization of CdS film and to the formation of CdS x Te1−x (x∼0.95) solutions at the interface. [Copyright &y& Elsevier]

Processes of self-organization play a key role in the development of innovative functional nanocomposites, allowing, in particular, the transformation of metastable solid solutions into multilayers by activating spinodal decomposition instead of layer-by-layer film growth. We report the formation of strained layered (V,Ti)O 2 nanocomposites in thin polycrystalline films using a spinodal decomposition. Already during the growth of V 0.65 Ti 0.35 O 2 films, spinodal decomposition was detected while producing atomic-scale disordered V- and Ti-rich phases. Post-growth annealing enhances compositional modulation, arranges the local atomic structures of the phases, and yields periodically layered nanostructures that resemble superlattices. The coherent interfacing of the V- and Ti-rich layers results in the compression of the V-rich phase along the c -axis of the rutile structure and enables strain-enhanced thermochromism. The latter is characterized by a simultaneous decrease in the temperature and width of the metal-insulator transition in the V-rich phase. Our results provide proof-of-concept for an alternative strategy to develop VO 2 -based thermochromic coatings by introducing strain-enhanced thermochromism into polycrystalline thin films.

The recent worldwide COVID-19 pandemic has highlighted the importance of a performant public sector in terms of health. To achieve greater use and efficiency of health information and communication technology (ICT), the whole community of European states needs a model to develop a common strategy to support the implementation of e-health and reduce decision-making difficulties. Our research suggests such a model, starting from the level of adoption to the implementation of e-health and points out the existing disparities in the European countries regarding the difficulties of adopting e-health. We draw a composite index to assess the inequalities present in the quality of life, the public health system, and the adoption of e-health. Furthermore, to return to a hierarchy of European countries, the relative distance method (RDM) is applied by combining various classification criteria. The results identify the European countries with the highest levels of adoption (Denmark, Estonia, Spain, Sweden, Finland, and the United Kingdom), where e-health is routine, and the countries with the lowest levels of adoption (Greece, Lithuania, Luxembourg, Malta, Romania, and Slovakia), where e-health is not widespread. These results reveal critical implications in identifying solutions to reduce the gaps between countries, identifying public policies to support the adoption of e-health, and reducing difficulties in decision-making., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Luca, Mustea, Taran, Stefea and Vatavu.)

We report on a comprehensive theoretical and experimental investigation of thermal conductivity in indium-tin-oxide (ITO) thin films with various Ga concentrations (0-30 at. %) deposited by spray pyrolysis technique. X-ray diffraction (XRD) and scanning electron microscopy have shown a structural transformation in the range 15-20 at. % Ga from the nanocrystalline to the amorphous phase. Room temperature femtosecond time domain thermoreflectance measurements showed nonlinear decrease of thermal conductivity in the range 2.0-0.5 Wm -1 K -1 depending on Ga doping level. It was found from a comparison between density functional theory calculations and XRD data that Ga atoms substitute In atoms in the ITO nanocrystals retaining Ia-3 space group symmetry. The calculated phonon dispersion relations revealed that Ga doping leads to the appearance of hybridized metal atom vibrations with avoided-crossing behavior. These hybridized vibrations possess shortened mean free paths and are the main reason behind the thermal conductivity drop in nanocrystalline phase. An evolution from propagative to diffusive phonon thermal transport in ITO:Ga with 15-20 at. % of Ga was established. The suppressed thermal conductivity of ITO:Ga thin films deposited by spray pyrolysis may be crucial for their thermoelectric applications.