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Abstract: A new nanocomposite with conducting polypyrrole (PPy) confined in ordered mesoporous silica SBA-15 channels has been synthesized by an in situ polymerization technique. The resulting material was characterized by X-ray diffraction (XRD), N2 adsorption/desorption, high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectra (FT-IR) and thermogravimetric analysis (TGA). The results show that PPy is formed in the channels instead of coating the outer surface of SBA-15 and nanocomposite possesses well-ordered hexagonal structure. Further, nanocomposite particles were used as dispersed phase in silicone oil for electrorheological (ER) investigation. Suspension of PPy–SBA-15 displays notable ER characteristics under external electric fields. [Copyright &y& Elsevier]

Abstract: Mesoporous silica nanofibers and Ag-doped composite nanoribbons were synthesized by a facile combination of an electrospinning technique and the sol–gel method. Tetraethyl orthosilicate, polyvinylpyrrolidone (PVP), triblock poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide), copolymer Pluronic P123, and silver nitrate (AgNO3) were the components of sol for the production of Ag-doped hybrid silica ribbons. Heat removal of structure-directing agent P123 in the hybrid fibers at high temperatures resulted in a mesoporous morphology, and the degradation of PVP caused AgNO3 to convert into silver in the form of nanoparticles. The size and content of the particles in the hybrid ribbons could be controlled by the concentration of AgNO3 and thermal treatment conditions. Scanning electron microscopy, N2 adsorption–desorption isotherm, transmission electron microscopy, X-ray diffraction, and UV–Vis spectroscopy were used to characterize the composite ribbons. The catalytic activity of the ribbons was evaluated by reduction of methylene blue dye and found to be better than in previous studies. [Copyright &y& Elsevier]