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Abstract: Polycrystalline fluorine-doped SnO2 thin films with SiC x O y or Si x Sn y O2 barrier layer are deposited on glass substrates by atmospheric pressure chemical vapor deposition (APCVD) method. The effect of barrier layer on structure and electrical property of FTO films was investigated. Results show that the inserting of barrier layer, especially the SiC x O y layer, has led to the improved crystallinity and the enhanced preferential orientation along the (200) crystallographic plane. SnO2:F/SiC x O y /Glass films with larger grain size and a columnar growth structure exhibited lower resistivity (~4.9×10−4), higher reflectance in the mid-far-infrared region (~80%) and lower emissivity (0.16), while maintaining high transmittance in the visible range. The SiC x O y film has therefore been considered as a more ideal potential barrier layer for FTO thin film production. [Copyright &y& Elsevier]

Abstract: Bismuth tungstate (Bi2WO6) nanocrystals with the average size of ca. 12 nm had been successfully synthesized by a simple solvothermal method at 180 °C for 2 h. The as-synthesized Bi2WO6 nanocrystals were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV–vis diffuse reflectance spectra, and N2 adsorption–desorption measurements. The visible-light-driven photocatalytic activity of the sample was evaluated by photo-degradation of rhodamine-B (RhB) at room temperature, which is much higher than that of the hydrothermal synthesized Bi2WO6 square plates and the commercially available TiO2 (P-25). We believed that the high photocatalytic activity could be ascribed to the intrinsically small grain size and high surface-to-volume ratio associated with the Bi2WO6 nanocrystals. [Copyright &y& Elsevier]

Abstract: The size-controlled synthesis of barium titanate (BaTiO3) nanocrystals has been achieved by a hydrothermal route with Fe doping and ethylenediamine (en) addition. The as-synthesized BaTiO3 nanocrystals were characterized with XRD, SEM, TEM, and HRTEM. The results revealed that the average particle sizes of Fe-doped samples were reduced compared to that of the sample without Fe doping, suggesting that the doping ions inhibited the crystal growth. It was also found that the average particle size decreased as the Fe doping concentration increased. Furthermore, the addition of en, which served as both solvent and capping agent, could suppress the particle growth and lead to the change in particle shape from sphere to cube by a confined effect. [Copyright &y& Elsevier]

Abstract: TiO2 nanodots can hopefully be used as optical devices, high performance sensor and highly active catalyst. The preparation of TiO2 nanodots with small dot size and high dot density on substrates becomes increasingly significant since small dot size can guarantee quantum effects and high activity, while high dot density can provide a basis for miniaturizing devices and increasing performance capacity. In this letter, high density TiO2 nanodots on Si substrate were prepared by a “microscopic mass-point addition” method. SEM images and XPS profiles revealed that pure TiO2 nanodots with high density (∼5×1011 cm−2) could be fabricated on Si substrate and the average dot size could be adjusted (8 nm∼11.5 nm) by temperature control of the substrate. It is suggested that the prepared high density TiO2 nanodots have great potential applications in fabrication of related devices. [Copyright &y& Elsevier]

Abstract: In this paper, we report a simple hydrothermal method without any surfactants, for the first time, to synthesize single-crystal BaTiO3 dendrites. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron diffraction (ED), and high-resolution transmission electron microscopy (HRTEM). The KOH concentration was found to be vital to the final formation of BaTiO3 dendrites. An obvious morphology evolution from sphere-like shape to dendrite was observed when KOH concentration was decreased from 1 M to 0.1 M. It is rational to expect that dendritic structures of other perovskite oxides may also be synthesized by this simple method. [Copyright &y& Elsevier]

Abstract: The BiCo x Fe1− x O3 samples have been successfully synthesized by hydrothermal process. The resulting products were characterized by X-ray powder diffraction (XRD), energy dispersive X-ray (EDS), differential thermal analysis (DTA), and physical property measurement system (PPMS).It was found that the magnetization of the obtained products was greatly enhanced by Co substituting for Fe ions. Furthermore, the value of magnetism of BiCo x Fe1− x O3 samples can be adjusted by Fe doping concentration. DTA curve indicates the ferroelectric properties of the obtained BCFO samples are not affected by Co substitution. Therefore, it would be interesting to realize thin films with similar compositions and study their properties in the interest of device applications. [Copyright &y& Elsevier]

Abstract: Spherical Pb0.70La0.30TiO3 (PLT30) fine powders of 125 nm in average particle size with cubic perovskite structure have been hydrothermally synthesized using KOH as mineralizer. The effect of KOH concentration on the phase and morphology of the as-synthesized fine powders was systemically investigated using characterization techniques such as XRD, TEM, SEM, SAED, and Raman spectra. The results indicated that a high KOH concentration was vital to obtain uniformly spherical PLT30 fine powders with stoichiometric ratio. When the KOH concentration was low, the final products were composed of particles with different shapes and compositions, which probably arose from the fact that lanthanum unequally incorporated into the lead titanate matrix. [Copyright &y& Elsevier]