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A novel N H TiO 2 photocatalyst was prepared via hydrothermal synthesis followed by a thermal treatment in NH 3 and H 2 atmospheres. The results showed that benzene with the initial concentration of 150 ppm (±5 ppm) could be thoroughly removed by N H TiO 2 under visible light irradiation. The influences of doping and hydrogenation on properties of TiO 2 samples were investigated. It is suggested that the disordered surface layer introduced by hydrogenation contributes to the excellent photocatalytic activity of N H TiO 2 . The synergistic effect of N doping and surface oxygen vacancies was also confirmed by ultraviolet–visible diffuse reflectance spectra and photoluminescence. Moreover, the diverse role of oxygen vacancies in different positions of TiO 2 has been focused on. [ABSTRACT FROM AUTHOR]

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: SiO2-coated martensite stainless steel nanoparticles were prepared using wire electrical explosion technique combined with sol–gel technique, and their structural and magnetic properties were studied. The coating silica on stainless steel nanoparticles was based on the use of silane coupling agent 3-mercaptopropyltrimethoxysilane (HS-(CH2)3Si(OCH3)3, MPTS) as a primer to render the stainless steel surface vitreophilic, thus rendering stainless steel surface compatible with silica. The control over the silica coating layer thickness can be achieved by varying the reaction time. For stainless steel nanoparticles, their saturation and remnant magnetizations decreased upon silica coating, and their saturation magnetizations obviously decreased with increasing the thickness of SiO2 coating layer. These stainless steel/silica core–shell nanoparticles can be utilized as precursors for making property-tunable magnetic nanoparticles, thin films, and multilayered core–shell structure nanocomposites. [Copyright &y& Elsevier]

Abstract: TiO2/CoFe2O4 composite nanoparticles with a core–shell structure have been obtained. The core CoFe2O4 nanoparticles were synthesized via co-precipitation method, and the shell TiO2 nanocrystals were derived via sol–gel technology followed by heat-treatment at 450 °C. The morphology and the crystalline structure of composite nanoparticles were characterized by transmission electron microscopy (TEM) and X-ray diffraction, respectively. The as-prepared composite particles can be utilized as a magnetic photocatalyst, which can be fluidized and recovered by an applied magnetic field enhancing both the separation and mixing efficiency for recyclable fluids. Magnetic properties and photocatalytic activities of these powders have been evaluated. [Copyright &y& Elsevier]

Abstract: In this work, 3D SnO2 with a hierarchical structure, which was built by numerous one-dimensional tetragonal prism nanorods, had been firstly synthesized by a facile one-step hydrothermal route at 200°C in the presence of cetyltrimethylammonium bromide (CTAB). The cationic surfactant CTAB played a key role in forming the 3D SnO2 hierarchical structure composed of nanorods. In addition, the novel SnO2 hierarchical structure exhibited good gas-sensing properties. The gas sensor showed good selectivity to ethanol gas. Moreover, a linear dependence of the sensitivity on the ethanol concentration was observed, it suggested that the sensor fabricated by SnO2 hierarchical structures is very suitable to detect ethanol with low concentration. [Copyright &y& Elsevier]