Search results for "chalcogenide"
showing 10 items of 141 documents
Atmospheric aging and surface degradation in As2S3 fibers in relation with suspended-core profile
2015
Abstract Microstructured optical fibers (MOF) can be seen as next generation fiber of significance in advancing the compact optics because of its excellent compatibility in integrated optics. However, the degradation of their physicochemical properties limits their efficiency and lifetime. Atmospheric moisture is responsible for the degradation of amorphous systems especially chalcogenide glasses. In the light of previously reported studies, in order to clarify the aging process continuously evolving in sulfide microstructured optical fiber over time, a detailed investigation of this phenomenon has been conducted. The time-dependent transmission and glass chemical deterioration have been st…
Chalcogenide Fibers for Mid-IR Light Generation: Potentialities and Drawbacks of the Microstructured Design in Sulfide Waveguides
2014
We study optical and structural aging in As2S3 microstructured optical fibers, submitted to room atmosphere that may have, among others, an impact on mid-infrared supercontinuum generation.
TaNi 2 .05Te 3 , eine Verbindung mit “aufgefüllter” TaFe 1+ x Te 3 ‐Struktur
1994
TaNi2.05Te3, a Novel Telluride with “Stuffed” TaFe1+xTe3 Structure The novel metal-rich layer compound TaNi2.05Te3 was synthesized from the elements. Its structure contains TaNi2Te3 layers which are interconnected by Ni atoms on partially occupied tetragonal-pyramidal sites located between the layers. The title compound and the related telluride TaFe1.14Te3 form a pair of compounds differing only in the occupation or nonoccupation of one 3d-material atom site. Therefore, the structure of TaNi2.05Te3, which is stabilized by interstial Ni atoms, can be regarded as a “stuffed” TaFe1.14Te3 type. Pairs of compounds with a similar structural relationship seem to be of general importance in early …
Growth Mechanism and Surface Functionalization of Metal Chalcogenides Nanostructures
2014
Following the discovery of carbon fullerenes and nanotubes (NTs), nanostructured materials and their synthesis have attracted tremendous attention due to their superior mechanical properties, their unique electronic behavior, and their high potential in making technologically advanced nanodevices. Among different classes, layered metal chalcogenides nanostructures are of interest for a variety of applications ranging from nanoelectronics or as source materials for energy applications, nanotribology and in heterogeneous catalysis. These nanoparticles are metastable phases. Therefore, equilibrium methods are necessary to prevent the formation of the thermodynamically stable bulk phase. On the…
From Single Molecules to Nanoscopically Structured Functional Materials
2006
AbstractThe synthesis of MS2 (M = Mo, W) onion-like nanoparticles by means of a high temperature MOCVD process starting from W(CO)6 and elemental sulfur is reported. The reaction can also be carried out in two steps where the intermediate amorphous WS2 nanoparticles formed through the high temperature reaction of tungsten and sulfur in the initial phase of the reaction are isolated and converted in a separate annealing step to onion-type WS2 nanoparticles. Based on a study of the temperature dependence of the reaction a set of conditions could be derived where onion-like structures were formed in a one-step reaction. Onion-like structures obtained in the single-step process were filled, whe…
Effect of Mn Doping on the Optical Properties of Chalcogenide Compounds ZnS and ZnTe
2020
In this paper, the influence of the addition of Mn on the optical properties of the binary compounds ZnS and ZnTe deposited by a close-spaced vacuum sublimation method onto nonoriented glass at different substrate temperatures was considered. The spectral dependences of the transmittance T (λ), reflectance R (λ) and the absorption α (λ), as well as the bandgap for each material (Eg) were measured and calculated.
Preparation and Characterization of Tungsten Chalcogenide Photocatalysts
1997
Tungsten chalcogenides powders have been prepared by sulfidation of WO3 with gaseous H2S. Different mixed WS2/WO3 systems have been obtained by varying the amount of initial WO3 powder, the time, o...
3.5-μm bandwidth mid-infrared supercontinuum generation in a 2-cm long suspended-core chalcogenide fiber
2014
A supercontinuum source extending from 0.6 to 4.1 µm has been successfully generated in a 2-cm long As2S3 chalcogenide suspended-core fiber by means of a nJ-level 200-fs pumping at 2.5 µm.
ChemInform Abstract: Preparation and Characterization of Tungsten Chalcogenide Photocatalysts.
2010
Tungsten chalcogenides powders have been prepared by sulfidation of WO3 with gaseous H2S. Different mixed WS2/WO3 systems have been obtained by varying the amount of initial WO3 powder, the time, o...