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This study reports the synthesis of quaternary copper nickel tin sulfide (Cu2NiSnS4) thin films using two different strategies and their physico-chemical properties. The first strategy includes co-evaporation of copper–nickel-tin–sulfur (CNTS) followed by sulfurization and the secondstrategy includes co-evaporation of copper–nickel–tin (CNT) followed by sulfurization. The X-ray diffraction (XRD) study reveals that the film prepared by both strategies has a polycrystalline Kesterite structure. The scanning electron microscope (SEM) analysis shows densely covered CNTS all over the substrate. The optical analysis of both CNTS films exhibits absorption of visible wavelength in an optimal range. The CNTS thin film synthesized using thermal evaporation technique followed by sulfurization has the potential to exhibit better photovoltaic properties for solar cell applications. [ABSTRACT FROM AUTHOR]

In this study, in order to obtain the optimal fabricating condition, the influences of heating temperature and time on the fabrication of zinc oxide (ZnO) nanowires are clarified. During this process, the synthesis and scanning electron microscope (SEM) images of ZnO nanostructures, produced by direct heating of metallic zinc, are presented. Besides, the SEM images and X-ray diffraction (XRD) patterns of products under different conditions are compared to analyze the surface morphology and composition of products. In the final observation, the best diameters of ZnO nanowires are achieved as 60–70 nm, which can be successfully applied as a substrate in Raman measurement. The optimal temperature is 450∘C, as well as the optimal time is 40–50 min. [ABSTRACT FROM AUTHOR]

The process of conversion from -Ga2O3 single crystal to gallium nitride (GaN) in an atmosphere of NH3 by chemical vapor deposition is investigated. The surface morphology and microstructure of the GaN nanoparticles are observed by scanning electron microscope, which indicates that the growth of GaN is via the Volmer-Weber mechanism. The -Ga2O3 is firstly evaporated at high temperature to form the porous layer, followed by the surface-defect induced GaN nucleation formation. The crystalline structure and epitaxial relationship of the GaN nanoparticles are investigated by X-ray diffraction (XRD) via -, showing GaN (0002) and (0004) diffraction peaks in the XRD spectra. It is concluded that the polycrystalline GaN film with hexagonal structure has a strong c-axis preferential orientation. [ABSTRACT FROM AUTHOR]

The effect of rare earth element neodymium (Nd) addition on the microstructure and martensitic transformation behavior of NiTiNd ( = 0, 0.1, 0.3, 0.5 and 0.7 at.%) shape memory alloy was investigated by scanning electronic microscope, X-ray diffraction and differential scanning calorimetry. The results show that the microstructure of Ni-Ti-Nd ternary alloy consists of NiNd phase, NiTi2 and the NiTi matrix. A one-step martensitic transformation is observed in the alloys. The martensitic transformation temperature Ms increases sharply increasing 0.1-0.7 at.% Nd content is added. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the effect of Mn doping on the electrical properties of ZnO thin films. ZnO thin films with different amounts of Mn concentrations (0, 5, 10 and 15 mol.%) were prepared by spray pyrolysis technique. The crystal structure was examined by X-ray diffraction (XRD) analysis. XRD patterns showed that all the samples were crystallized in wurtzite structure while a decrease in crystallinity and switch in preferential orientations were observed in Mn-doped thin films comparing to undoped ZnO. The element composition of all thin films was detected by energy dispersive X-ray (EDX). The surface morphology of the films was investigated using field emission scanning electron microscope (FESEM) and optical properties were studied using UV-vis spectroscopy. UV-vis study revealed that the band gap blueshifts with the increase in Mn content and increases with the increase in Mn concentration. The resistivity and activation energy were measured at room temperature and ranging from 373 K to 573 K. Comparing to undoped ZnO thin film, the resistivity of Mn-doped ZnO films increased because of different parameters such as increasing barrier height energy and reducing the oxygen deficiency. [ABSTRACT FROM AUTHOR]