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Abstract: Large quantities of single crystalline magnesium borate nanowires of the form Mg2B2O5 with typical diameter about 120–180nm and length about 0.2mm have been successfully synthesized by a new and simple method of heating the mixed tablet of Mg(BO2)2 and graphite directly in vacuum at 1200°C for 1h. The products have been characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectrometry and selected area electron diffraction. The process of the nucleation and the growth of nanowires have been analyzed by VS mechanism. The results of the lubricating properties show that the friction coefficient of the oil is significantly decreased by the addition of Mg2B2O5 nanowires. Our results indicate that the new method we use is effective in synthesis of Mg2B2O5 nanowires and the nanowires can be used as additive to antiwear nanodevices. [Copyright &y& Elsevier]

Abstract: The composite of hollow glass microspheres coated by SnO2 nanoparticles has been successfully fabricated via sol-gel method. The phase structures, morphologies, particle size, shell thickness, chemical compositions of the composite have been characterized by XRD, FESEM, and EDX. The results show that SnO2 coating on hollow glass microspheres can be achieved, and the coating layers are constituted by SnO2 nanoparticles of mean size ca. 15 nm. The SnO2 coating layers grow thicker with the increased concentration of SnCl4. The effects of parameters (reaction temperature, concentration of NaOH and SnCl4, and time) were investigated to yield SnO2 coating on hollow glass microspheres, and the UV–vis absorption spectra of the composites were studied. [Copyright &y& Elsevier]

Abstract: The composites of hollow glass microspheres (HGMS) coated by zinc oxide (ZnO) nanorods (HGMS/ZnO) were obtained by the controlled doubled-jet precipitation method in an ethanol–water solution. The particle-size, morphology, crystal structure and optical properties of the as-prepared HGMS/ZnO composites were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and room-temperature photoluminescence (PL) spectra. Moreover, we propose the mechanism that the hollow glass microspheres are modified with triethanolamine to obtain ZnO-coated composites. This method can also be applied to other substrates forming continuous films with highly ordered ZnO nanorods across the films. [Copyright &y& Elsevier]