The transition metal fluorides KMF3 (M = Mn, Co, and Ni) were synthesized through a simple solution route. The crystal structure, morphology and electrical transport property of the resulting products were investigated. The compound KMF3 crystallizes in a cubic perovskite structure with space group Pm-3m (No. 221). A crystal structure of KMF3 was refined by the Rietveld method based on the X-ray powder diffraction data. The unit-cell parameters are 4.189 46(4), 4.075 58(4), and 4.025 70(2) for KMnF3, KCoF3 and KNiF3, respectively. A metal–insulator transition was observed in temperature-dependent electrical transport characterization in the temperature range from 250 to 280 K for these three compounds, which is considered to be related to spin-exchange in this kind of material.

The c-oriented La1.8Sr0.2CuO4 and La1.9Sr0.1CuO4 bilayer films were deposited on (001) SrTiO3 single-crystal substrates by using the pulsed laser deposition technique. The effects of deposition parameters on the quality of thin films were investigated. The crystal structures and surface morphologies were characterized by means of XRD and SEM, and the results showed that an as-prepared film deposited with the optimized parameters has high quality. Then La1.8Sr0.2CuO4/La1.9Sr0.1CuO4 bilayers structure was prepared using the optimized parameters for each corresponding layer, and the electrical transport properties were measured. Interesting rectifying properties were observed at both room and low temperatures, and the rectifying ratio at low temperature was found to be much higher than that at room temperature.

Ni nanowire arrays were prepared by electroplating using anodic aluminum oxide templates, and a magnetic field was applied during the electroplating process. The effects of an applied magnetic field on the texture and magnetic properties of the Ni nanowire arrays were studied. The results show that the (110) texture is formed in the nanowires prepared in different magnetic fields. However, the applied magnetic field during electroplating can affect the texture degree, and there exists a suitable magnetic field for small diffusion degree of the (110) texture. On the basis of texture characterization, the effects of applied magnetic field on the magnetic properties of Ni nanowire arrays are discussed.

Nanostructuring is one of the effective approaches to lower the thermal conductivity of thermoelectric materials for improving its figure of merit. The nano-sized uniform skutterudite Co1−xNixSb3 (x = 0, 0.05, 0.075, 0.125, 0.15, and 0.25) thermoelectric powders were synthesized in triethylene glycol solution by using CoCl2, NiCl2, and SbCl3 as precursors and NaBH4 as the reductant. Different synthesis conditions were studied to pursue pure and uniform skutterudite CoSb3 powders. The powders were characterized by X-ray diffraction, field emission scanning electron microscope, and energy-dispersive X-ray analysis. Experimental results show that a Ni-doped skutterudite Co1−xNixSb3 single phase was obtained at 290 °C for 12 h. The powders are spherical, small, and uniform. As x increases from 0 to 0.25, the unit-cell parameter a increases from 0.9044 to 0.9065 nm and the particle size increases from 10 to 30 nm.

Martensitic transformation and magnetic entropy change in Co substituted Ni50Mn35−xCoxSn15 (x = 0, 1.0, 1.5, 2.0, and 3.0) Heusler alloys have been investigated by X-ray powder diffraction analysis, differential scanning calorimetry, and magnetic measurements. X-ray diffraction analysis reveals that the Ni50Mn35−xCoxSn15 alloys have L21 Heusler structure at room temperature. The phase decomposition of the sample with x = 3.0, after annealing 48 h at 1173 K, is confirmed by both X-ray powder diffraction analysis and energy-dispersive x-ray spectroscopy in scanning electron microscopy. With the increase of the Co content from 0 to 2.0, the martensitic transformation temperature TM increases from 185 to 245 K, which is in good agreement with the rule of valence electron concentration e/a-dependence of TM. The magnetic entropy change ∆SM is investigated in the vicinity of the martensitic transformation.

Cu(In,Ga)Se2 (CIGS) semiconductors were prepared by arc melting and the vacuum solid reaction. CIGS nanoparticles were synthesized by the mechanical alloy method. The influences of various ball-milling speeds on phase structures for CIGS nanoparticles were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The crystal structures and unit-cell parameters of CIGS nanoparticles were determined using TREOR program and the least squares method. A Rietveld structural refinement was used to determine the atomic occupations and atomic numbers of CIGS prepared under various ball-milling speeds. The least size of agglomerated CIGS nanoparticles should be around 200 nm. CIGS nanoparticles milled at various milling speeds with a tetragonal chalcopyrite structure were obtained according to XRD analyses. However, Ga content in CIGS depends on milling speeds. Based on the structural refinements, the unit-cell parameters are a = 5.693(8)–5.744(9) Å and c = 11.334(9)–11.524(4) Å with gallium content ranging from 0.3 to 0.5. The atomic occupations are corresponding to the 4a crystal site for Cu atoms, the 4b site for In and the 8d site for Se. Ga prefers to occupy the 4b crystal site.

In order to complete the research on the Fe–Se binary system, the phase structures with selenium contents from 50 to 60 at.% have been studied. Fe–Se binary samples used in this study were prepared by the high-temperature solid-state reaction method, and the phase structure of each sample was determined by powder X-ray diffraction. The solid solubility of the Fe3Se4 phase was determined to be from 56.1 to 57.6 at.% Se based on the values of unit-cell parameters. Magnetic properties of the samples were also studied.

Investigations into the morphology and structural evolvement of nanomaterials are essential for understanding the growth process. Herein, we present meaningful results on crystallinity transformation of β-SiC nanorods at different preparation temperatures using X-ray diffraction. Results of the characterization indicated that both crystallinity and yield of the as-prepared β-SiC nanostructures were enhanced with increasing reaction temperature. Scanning electron microscope and high-resolution transmission electron microscope were further employed to understand detailed structural information of the SiC nanorods obtained at specific temperature. The results may shed light on structural evolvement for fabrication of nanomaterials.

Eu3+-doped SmBa3B9O18 luminescent materials were synthesized by high temperature solid state reactions. The structure and photoluminescence properties of Sm(1−x)EuxBa3B9O18 (x = 0.2, 0.4, and 0.6) were investigated by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and photoluminescence spectra. The results show that doping of Eu3+ ions does not change the structure of SmBa3B9O18. The luminescence is mainly the characteristic Eu3+ ion luminescence. No concentration quenching processes occur with the increment of Eu3+ concentration. The work implies that SmBa3B9O18 is a potential host material and europium-doped SmBa3B9O18 may find application in display and optical devices.

The effect of Dy3+ doping at A-site in hexagonal YMnO3 on the microstructure and magnetic properties was studied. Polycrystalline Y1−xDyxMnO3 samples with x ranging from 0 to 1 were synthesized by the solid-state reaction method. The microstructures of all the samples were studied by X-ray diffraction, which shows that Y1−xDyxMnO3 with a low concentration (x ≤ 0.5) of Dy3+ retains a hexagonal symmetry. The crystal structure refinements of the hexagonal Y1−xDyxMnO3 using the Rietveld method show that the unit-cell parameters of a, c, and unit-cell volume increase with increasing Dy doping, while the MnO5 trigonal bipyramids remain almost unchanged. The remarkable increasing of magnetic moment at a low temperature with increasing the Dy3+ doping concentration is ascribed to the spin order of Dy3+ and the increasing Dy3+–Mn3+ coupling and Mn3+–O–O–Mn3+ interaction.