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Li-doped PbTiO 3 perovskite cubic particles were successfully synthesized via a facile and simple hydrothermal method by using lithium nitrate (LiNO 3 ) as additives. Due to the Li-doping, not only the particles become smaller but also some Ti 3 + ions and oxygen vacancies are brought about in the lattice of the PbTiO 3 perovskite. In consequence, the Li-doped PbTiO 3 samples exhibit excellent visible-light photocatalytic performance on the degradation of MB. [ABSTRACT FROM AUTHOR]

Stamen-like LiMnPO4 nanostructures self-assembled with nanorods along the [001] direction were successfully synthesized via a simple hydrothermal method. The crystalline structure, morphology and microstructure were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). A possible mechanism for the formation of LiMnPO4 nanorods and the assembly of the stamen-like nanostructures was proposed based on the experimental results. Additionally, the electrochemical performance of the stamen-like LiMnPO4 nanostructures as cathode materials in Li-ion batteries was also investigated through charge–discharge measurements and CV curves. [ABSTRACT FROM AUTHOR]

Single-crystal strontium titanate (SrTiO3) nanosheets have been synthesized via a solvothermal reaction route with ethylene glycol (EG) as reaction medium solvent. The as-synthesized SrTiO3 products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and high resolution transmission electron microscopy, respectively. The results show that the single-crystal SrTiO3 nanosheets are parallel to the (110) plane and self-assembled by primary nanocrystallites in monolayer. EG as a organic solvent plays an important role in the synthesis of the single-crystal SrTiO3 nanosheets. Based on the experimental results, a possible formation mechanism of the single-crystal SrTiO3 nanosheets has been proposed. [ABSTRACT FROM AUTHOR]

Abstract: Phase-controlled synthesis of bismuth ferrites has been achieved via hydrothermal route by adjusting the KOH concentration. The as-prepared powders were characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and selected area electron diffraction. The particle morphologies of the as-prepared powders evolve from nanoflakes, to self-assembled particles, and microparticles when the concentration of KOH was changed from 1.5M, 2.5M, to 3.5M, and 5M. Correspondingly, the main phase of the samples changed from orthorhombic Bi2Fe4O9, both Bi2Fe4O9 and BiFeO3, to pure rhombohedral BiFeO3. On the basis of these experiments, the phase formation and morphology evolution mechanism of the samples are discussed. Furthermore, the photocatalytic activity of the as-prepared samples was investigated by the photo-degradation of rhodamine-B solution. [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: Uniformly distributed PbTiO3 nanodots were successfully prepared by phase separation approach. A precursor sol film was first spin-coated on Si wafer and then spontaneously separated into two distinct phases owing to the Marangoni instability. PT nanodots with tailorable size and density were obtained after further heat treatment. X-ray diffraction analysis indicated that these nanodots showed a perovskite structure. An excellent room temperature field emission property of PbTiO3 nanodots was observed: the minimum turn-on voltage was about 5.3V/μm; while the emission current density reached about 270μAcm−2 at an applied field of about 9.25V/μm. [Copyright &y& Elsevier]

A new method has been developed to synthesize barium titanate (BaTiO3) nanoparticles with a narrow size distribution under ambient conditions at room temperature. The as-prepared BaTiO3 nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, high-resolution TEM, and selected area electron diffraction. On the basis of the characterizations, it was found that the particle size could be easily tuned by adjusting the experimental parameters, such as the solvent component and reaction time. The basicity of the organic solvent was considered to play an important role in the room-temperature synthesis and the solvent molecules had a strong influence on the crystal growth of BaTiO3 nanoparticles. The BaTiO3 nanoparticles obtained were well dispersed and possessed a cubic perovskite structure at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: Well-crystallized single-crystal BiFeO3 (BFO) nanoflakes have been successfully synthesized for the first time by the hydrothermal method assisted by KNO3. The as-prepared samples were characterized by X-ray powder diffraction (XRD), transmission electron microscope (TEM), high-resolution TEM (HRTEM), and physical property measurement system (PPMS). It was found that KNO3 played a key role in the formation of BFO nanoflakes. The as-prepared BFO nanoflakes were single-crystal in structure and showed super paramagnetic behavior at room temperature. It is expected that this process may be extended to the synthesis of other kinds of nanostructure materials, which will be beneficial to their detailed experimental investigation of the size- and morphology-dependent properties. [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: Bi2Fe4O9 (BFO) nanoparticles were successfully synthesized by a hydrothermal method at a temperature as low as 100°C. The as-prepared powders, characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), transmission electron microscope (TEM) and physical property measurement system (PPMS), exhibited a pure BFO phase about 100nm size with uniform sheet-like shape and exhibited an AF order at room temperature. It was found that high alkali concentration and alkali ion Na+ played a key role in the formation of BFO nanoparticles at a low temperature of 100°C. [Copyright &y& Elsevier]

Abstract: BFO nanoparticles were successfully synthesized by a polymer assisted hydrothermal method at a temperature as low as 160°C. The as-prepared powders, characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM), exhibited a pure BFO phase about 10nm size and uniform sphere-like shape. It was found that the added polymer played a key role in decreasing the growing speed of BFO nuclei and resulted in the formation of BFO nanoparticles. [Copyright &y& Elsevier]

Abstract: Single-crystal PbTiO3 nanorods have been synthesized by phase transformation from Pb2Ti2O6 nanorods. In the process, single-crystal Pb2Ti2O6 nanorods were first prepared by hydrothermal method, and single-crystal PbTiO3 nanorods were obtained by phase transition from the resultant Pb2Ti2O6 nanorods. Various approaches including XRD, Raman, TEM, SAED, and HRTEM were used to investigate the as-prepared products. It was found that Pb2Ti2O6 nanorods played a key role in the formation of PbTiO3 nanorods. [Copyright &y& Elsevier]