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This study concerns structural and optothermal properties of iron ditelluride layered structures which were fabricated via a low-cost protocol. The main precursors were FeCl3·6H2O and Fe2O3. After a heat treatment within a tellurium-rich medium at various temperatures (470°C, 500°C, and 530°C) during 24 h, classical analyses have been applied to the iron ditelluride layered structures. A good crystalline state with a preferential orientation of the crystallites along (111) direction has been recorded. Moreover, additional opto-thermal investigation and analyses within the framework of the Lattice Compatibility Theory gave plausible explanation for prompt temperature-dependent incorporation of tellurium element inside hematite elaborated matrices. [ABSTRACT FROM AUTHOR]

Abstract: In2S3 thin films have been synthesized by annealing indium thin films under sulfur pressure. The indium thin films have been deposited by evaporation onto glass substrates. The sample is then introduced, with small grains of sulfur into a Pyrex tube. The latter is sealed under vacuum and then annealed for two hours at temperatures ranging from 280 ∘C to 400 ∘C in a step of 40 ∘C.This simple and economic technique allows the elaboration of In2S3 thin films crystallized in the structure. Optical density (O.D.) measurements were made for In2S3 thin films synthesized at different temperatures. The optical spectra show that the threshold value of optical absorption is approximately 610 nm. By increasing the synthesis temperature this threshold value moved towards higher wavelength values. The gap is around 3 eV and the electrical resistivity measurements at room temperature, show that the films are highly resistive with an electric conductivity around 10−1 (Ωcm)−1. [Copyright &y& Elsevier]

Abstract: In this study, WO3 thin films were grown on glass substrates using an aqueous solution containing tungstate (NH4)2WO4 as precursor. The substrate temperature incremented from 250 to 500°C, by steps of 50°C. The structural properties were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. Microprobe analyses showed that a balanced stoichiometric composition was obtained for thin films prepared at T s =350 and 400°C. The X-ray diffraction analyses showed different structure crystallography in function of the substrate temperature. Moreover, films deposited at 400°C were annealed in air for 2h at 450 and 500°C, respectively and the structural changes due to heat treatment were studied. Finally, the optical properties of these films were carried out using optical measurements of transmittance T(λ) and reflectance R(λ) spectra in 300–1800nm domain. The refractive and absorption indexes, n and k were calculated. The band gap energy value was found lying in 2.6–3.6eV domain. [Copyright &y& Elsevier]