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BiFeO3 (BFO) nanoparticles were successfully synthesized by a hydrothermal method assisted by a mineralizer at as low a temperature as 200°C. The products were characterized by X-ray powder diffraction, transmission electron microscope, and physical property measurement system. It was found that KNO3 as a mineralizer played an important role in the formation of BFO nanoparticles, and the as-synthesized BFO nanoparticles showed an enhanced ferromagnetism at room temperature. [ABSTRACT FROM AUTHOR]

Ni@Ag core shell nanowires (NWs) were prepared by in situ chemical reduction of Ag+ around NiNWs as the inner core. Different Ni@Ag NWs with controllable morphologies were achieved through the layer-plus-island growth mode and this mechanism was confirmed by scanning electron microscopy, X-ray fluorescence, and X-ray photoelectron spectroscopy analyses. When used as a catalyst, the synthesized Ni@Ag NWs exhibited high reduction efficiency by showing a high reaction rate constant k of 0.408 s−1 in reducing 4-nitrophenol at room temperature. Besides, combining the magnetic property, including high saturation magnetization and low coercivity, the magnetic NiNW core contributes to excellent recyclability and long-term stability with only a 2.2% performance loss after 10 recycles by magnets. The Ni@Ag NWs proposed here show unprecedentedly high potential in applications requiring high efficiency and a recyclable catalyst. [ABSTRACT FROM AUTHOR]

Position- and density-controlled ZnO nanorod arrays (ZNAs) were successfully grown on a Si substrate through a low temperature (90 °C) hydrothermal approach assisted by pre-formed ZnO micro/nanodots. The ZnO dots on Si substrates were prepared by a spin-coating technique, through which the pattern and density of the dots could be easily changed. Accordingly, the position- and density-controlled growth of ZNAs was achieved. For the resulting density-controlled ZNAs, the density could range from (5.6 ± 0.01) × 102 to (1.2 ± 0.01) × 102 rods µm[?]2. The room-temperature photoluminescence (PL) spectrum of ZNAs exhibited excellent UV emission. The water wettability measurements of the ZNAs with different density showed good hydrophobicity, and the ZNAs with the lowest density revealed a superhydrophobic characteristic with a water contact angle of 166.1°. [ABSTRACT FROM AUTHOR]

A facile route to prepare two-dimensional ZnO nanosheet structures on Si substrates was developed through the adoption of a ZnO seed-layer and suitable growth medium in this work. The characterization results showed that ZnO nanosheets could be grown on Si substrates with a pre-formed ZnO seed-layer at room temperature. The ZnO nanosheets, with thickness of 20-25 nm, were interwoven into networks to form a continuous nanosheet film. Room-temperature measurements of the photoluminescence (PL) spectra and water wettability for the resulting ZnO nanosheet structures showed high intensity ratio of the UV emission to the defect emissions and good hydrophilic property without UV illumination. The present work demonstrates that the adoption of a ZnO seed-layer is an effective approach for room-temperature growth of ZnO nanosheets grown on substrates. [ABSTRACT FROM AUTHOR]

High-density single-crystalline orthorhombic TiSi nanorods and nanopins have been successfully prepared for the first time on a Ti5Si3layer by chemical vapor deposition, using SiH4and TiCl4as the precursors. The quadrate nanorods are approximately 0.5 µm long and 30 nm × 30 nm in area. The nanopins are 0.7-1 µm long in total, with the quadrate tip about 200 nm long and 50 nm × 50 nm in area. The TiSi nanorods and nanopins grow along the [110] direction of the orthorhombic TiSi crystal from the bottom, with the tip being pushed upwards. The growth process can be defined as a self-induced growth. The self-induction mechanism addressed here expands our understanding of growing nanostructures. [ABSTRACT FROM AUTHOR]

The multilayered Silica@Zn--Sr@Silica nanospheres were fabricated by a layer-by-layer (LbL) assembly route, and controlled release of active trace ions can be enhanced by low-frequency ultrasound, which is potentially advantageous not only to multicomponent administrating but also to elicit synergistic effect for promoting tissue regeneration combined the trace ion activity with ultrasound physical stimulus. [ABSTRACT FROM AUTHOR]

Ti-doped barium ferrite powders BaFe12−xTixO19 (x = 0, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8) were synthesized by the sol–gel method. The phase structure and morphology were analyzed by x-ray diffraction (XRD) and scanning electron microscopy, respectively. The powders were also studied for their magnetic properties and microwave absorption. Results show that the Ti-doped barium ferrites (BFTO) exist in single phase and exhibit hexagonal plate-like structure. The anisotropy field Ha of the BFTO decreases almost linearly with the increase in Ti concentration, which leads to a shift of the natural resonance peak toward low frequency. Two natural resonance peaks appear, which can be assigned to the double values of the Landé factor g that are found to be ~2.0 and ~2.3 in the system and can be essentially attributed to the existence of Fe3+ ions and the exchange coupling effect between Fe3+ and Fe2+ ions, respectively. Such a dual resonance effect contributes a broad magnetic loss peak and thus a high attenuation constant, and leads to a dual reflection loss (RL) peak over the frequency range between 26.5 and 40 GHz. The high attenuation constants are between 350 and 500 at peak position. The optimal RL reaches around −45 dB and the practicable frequency bandwidth is beyond 11 GHz. This suggests that the BFTO powders could be used as microwave absorbing materials with extraordinary properties.