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Bi₂S₃ nanocrystals with different shapes were synthesized via a simple solventothermal route. Nanorods and nanotubes can be obtained by changing reaction temperature. In the presence of surfactant, hollow nanospheres can be produced. The nanocrystals were characterized by X-ray powder diffraction and transmission electron microcopy. The growth mechanisms were discussed.

Wafers of crystalline silicon (c-Si) and compound semiconductors (GaP, GaAs) were nanostructured by using the electrochemical etching in specially designed cells with two or more electrodes spaced at 100–500 μm distances, which allowed keeping the electrolyte due to capillary forces. Investigations by means of atomic force microscopy and optical spectroscopy revealed nanoporous and nanocrystalline structure of the prepared samples. The employed capillary-force-assisted method is promising for preparation of thin layers of nanostructured semiconductors with desired optical properties having advantages of cost saving, quickness and flexibility in the electrical contact arrangements versus conventional electrochemical etching methods.

ZnO nanowires (NWs), grown by hydrothermal and vapor phase transport (VPT) methods, were employed as the channel layers to fabricate single nanowire Field Effect Transistors (NWFETs) with a p⁺-silicon as the bottom gate. The FET employing hydrothermal grown ZnO NWs shows n-type depletion mode with a field mobility of 18.27 cm²/V⋅s, an on/off ratio of 10⁶, and a threshold voltage of -48.5 V. In comparison, the device using VPT grown NWs operates in n-type depletion mode with a field effect mobility of 36.94 cm²/V⋅s, a drain current on/off ratio of 10⁵, and a threshold voltage of -14 V. The reason for the difference of threshold voltage and the mobility by two methods was discussed in this paper.

70 MeV Si ions irradiation at the liquid nitrogen temperature (77 K) induced nanoclustering on GaN epilayers grown by Metal Organic Chemical Vapor Deposition (MOCVD) are reported. HRXRD rocking curves show that there are no localized amorphization due to irradiation. Atomic force microscopy images reveal the formation of nanoclusters on the surface of the irradiated samples. On increasing the fluence the number of modified regions on the surface increases and resulted in three dimensional growth of nanocluster due to overlapping and coalescence. X-ray photoelectron spectroscopy (XPS) studies confirm that the surface features are composed of GaN. The variation of carrier concentration and hall mobility with respect to ion fluence are also studied. The effects of ion-beam induced modifications on the structural, surface characteristics and electrical properties of GaN are studied and possible mechanisms responsible for the modifications are discussed.

Ruthenium doped zinc oxide was synthesized by a simple sol–gel method via ultrasonication. The samples were characterized by X-ray diffraction, high resolution scanning electron microscopy (HR-SEM), high resolution transmission electron microscope (HR-TEM), energy dispersive spectroscopy (EDS) and UV-visible spectroscopy techniques and tested for the feasibility as a heterogeneous photocatalyst. The photocatalytic activity of Ru doped ZnO was tested using an azo dye, congo red (CR) in an aqueous solution, as a model compound. For comparison, the photocatalytic activity of pure ZnO was also performed. The parameters studied include the effect of initial CR concentration, photocatalyst weight and charge transfer phenomenon. The observed reaction mechanism was rationalized based on the elementary chemical reaction occurring in the irradiated heterogeneous reaction mixture. Total mineralization of CR was observed for both pure and Ru doped ZnO system. However, the photocatalytic activity of Ru doped ZnO was found to be higher than that of a pure ZnO.

There has been a recent uptick in interest in hybrid solar cells, which use polymeric organic materials with semiconductor nanoparticles in the active layer. In this paper, hybrid material is prepared by physical mixing of tri-ethanol amine capped CdSe CdSe-TEA nanoparticles with poly($o$-toluidine). Material properties of organic-inorganic hybrid materials can be tuned by changing the ratio between them. The optical properties of the hybrid compound were evaluated through ultra-violate–visible spectroscopy UV–Vis. The influence of CdSe nanoparticles weight percent on the electrical properties of hybrid thin films has been investigated. The conductivity of the hybrid films increases with the increasing CdSe content, and then decreases with excess CdSe content.