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Influences of preparation conditions on the formation and depth dispersion of Ag nanoparticles in soda – lime silicate glass were systematically studied by using ultraviolet–visible (UV–vis) spectrophotometer, X-ray photoelectron spectroscope (XPS), electron microprobe analyzer (EMA) and transmission electron microscope (TEM). The results indicate that the dispersed depth of Ag nanoparticles mainly depends on the diffusion depth of Ag + ions in the ion-exchanged glass, and Ag nanoparticles have a reduced volume-filling fraction (VFF) along the depth. The VFF of Ag nanoparticles increases with increasing the concentration of Ag + ions in the glass, the annealed temperature and/or the annealed duration. Ag nanoparticles form easier in Fe-containing glass than in Fe-free glass. Annealing the ion-exchanged glass in H 2 atmosphere favors the formation of Ag nanoparticles at a lower temperature and a shorter duration than in air. Ag nanoparticles display a narrow size distribution of 1–6 nm in the annealed sample in air and a broad size distribution of 1–30 nm in the annealed sample in H 2 atmosphere. The formation mechanism of Ag nanoparticles in the ion-exchanged glass is discussed in detail. [ABSTRACT FROM AUTHOR]

Cu-Ag nanoparticles have been successfully synthesized by one-pot solvothermal treatment of a mixture of AgNO and Cu(OAc)·HO in ethylene glycol solution at 180 °C for 10 h. The samples were characterized by UV-visible absorption, X-ray diffraction (XRD), and extended X-ray absorption fine structure (EXAFS) spectroscopy, transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). The results showed that Cu-Ag nanoparticles and a small amount of phase-separated Cu-Ag alloy nanoparticles with an average diameter of 100 ± 30 nm were synthesized by the solvothermal treatment procedure. The mechanism of formation is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Ordered anatase TiO2 nanotubes (TiO2 NTs) on Ti substrate were synthesized by electrochemical anodization and subsequently vapor-thermal treatment. Ag nanoparticles were decorated on TiO2 NTs by successive ionic layer adsorption and reaction (SILAR) technique. Raman spectroscopy, X-ray absorption near edge spectroscopy (XANES), X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for the characterization of surface morphology, phase composition, and microstructure of the original TiO2 NTs, the vapor-thermally treated TiO2 NTs and the Ag nanoparticles decorated TiO2 NTs. The results indicate that vapor-thermal treatment favors to the transformation of amorphous TiO2 into anatase phase. Increasing the SILAR cycle times favors to increase the loaded amounts of Ag nanoparticles in TiO2 NTs. Ag nanoparticles are uniformly distributed in the TiO2 NTs, and the SILAR process does not damage the ordered tubular structure. A possible formation mechanism of Ag/TiO2 NTs has also been proposed. The photocatalytic results showed that the Ag nanoparticle modified TiO2 NTs largely enhanced the photocatalytic degradation of methyl orange under ultraviolet light irradiation. [Copyright &y& Elsevier]