Papers by Keyword: Dichalcogenides

Abstract: 2D nanosheets/ nanoparticles based MoS₂/TiO₂ nanocomposites were prepared in different weight compositions which were further employed to investigate photocatalytic degradation of methylene blue. Anatase TiO₂ powder was prepared via sol-gel reflux method using titanium tetraisopropoxide as Ti precursor. MoS₂/TiO₂ nanocomposites were prepared by in situ addition of exfoliated MoS₂ (2D-nanosheets) in different weight ratios of 0.1%, 0.5%, 1%, 2% and 5% in TiO₂ sol. Surface morphology, phase analysis, optical properties were studied using SEM, XRD, UV-Vis spectroscopy respectively. SEM results showed that TiO₂ nanoparticles were completely adsorbed over the surface of MoS₂ sheets as reflux synthesis was employed. Efficient charge carrier separation was achieved which reduced recombination, and hence, enhanced photo-degradation of methylene blue was observed. The hetero-structures showed less operation time in sunlight for photodegradation of methylene blue and a highest rate constant was observed by 2 wt.% loading of MoS₂ on TiO₂. These composites can also be used commercially as they show promising results.

Abstract: The two dimensional nanoplates of WSe2 and MoSe2 are the result of solid-state thermal (750oC) reaction between micrometer-sized W or Mo with micro-size Se powder under inert atmosphere via carving phenomena in a closed reactor. This is a distinct top-down approach presented for the fabrication of inorganic nanoplates, where micron-sized metal particles having very high melting and boiling points are converted into a Se–M–Se sandwich structure employing a single-step, scalable, and environmentally- friendly chemical reaction under autogenic pressure at elevated temperature (RAPET). The mechanistic elucidation of the creation of WSe2/MoSe2 nanoplates is suggested on the basis of the crystal structure with the support of data obtained from compositional, structural, and morphological characterizations.

Abstract: The Te doped NbSe2-xTex (x=0, 0.10, 0.20) single crystals were prepared by vapor transport method and the variations of structure and superconducting properties with Te content were studied. It is found that the Te substitution increases the degree of disorder and causes sharp decrease of superconducting transition temperature (Tc). The temperature dependence of upper critical field (Hc2) of pure NbSe2 crystal can be fitted by the two-band model, and the effect of Te substitution on Hc2(T) is discussed.