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ReO3 were prepared by thermal treatment of the macromolecular Chitosan·(ReCl3)X and PSP-4-PVP·(ReCl3)X precursors. The plasmon band in the visible region for the as obtained ReO3 from their visible spectra was observed at λmax of 640 nm. The nature of the polymeric precursor is acting as a solid state template and influences the size and morphology of the metal oxides. For the first time, the photocatalytic degradation of methylene blue using ReO3 was measured founding a moderated and high activity for ReO3 arise from Chitosan and PSP-4-PVP precursors respectively. The inclusion of ReO3 into SiO2 was performed using a combined solution of the Chitosan and PVP precursors by the sol–gel method. Subsequent pyrolysis of the solid precursors Chitosan·(ReCl3)X(SiO2)y and PSP-4-PVP·(ReCl3)X.(SiO2)y give rise to the nanocomposites ReO3//SiO2. The as obtained ReO3 nanoparticles inside SiO2 are small as 1 nm. The ReO3 nanoparticles are distributed uniformly inside the matrix of SiO2, leading to stable semi porous materials suitable for high temperature catalytic application. The composites ReO3/SiO2 exhibit a moderate photocatalytic activity toward the degradation of methylene blue and similar to that of ReO3. [ABSTRACT FROM AUTHOR]

In an effort to discover new inorganic UV absorbers, titania included into silica was prepared using a solvent-less solid state method involving the pyrolysis of the as prepared precursor Chitosan·(TiOSO4)/SiO2, as an alternative and versatile way to using these compounds for practical applications. The new TiO2/SiO2 composite was characterized by PXRD, SEM–EDS, TEM and UV–Vis absorption analysis. The SEM–EDS mapping images show a uniform distribution of TiO2 into the silica matrix. The optical properties of the composite have shown an interesting result related to high absorption of UVB rays and an improved absorption of UVA rays than pure TiO2. Efficient suppression of photocatalytic behavior of TiO2, when is incorporated into silica, was evidenced from 85 to 31%, suggesting it material as alternative inorganic UV absorber to remains the properties of the methylene blue dye. These results reveal their potential use in practical textile industry and UV protection agent to avoid human damage. [ABSTRACT FROM AUTHOR]

Bimetallic Au/Ag nanostructures have been included inside SiO by pyrolysis of the macromolecular complexes Chitosan·(MLn/M′Ln)·SiO and PSP-4-PVP·(MLn/M′Ln)·SiO with MLn = AuCl and M′Ln = Ag(CFSO). The structural characterization was performed by XRD (X-ray diffraction of powder) and UV-Vis, and the microstructural characterization was done by SEM/EDS analysis HRTEM. The resulting products from the pyrolytic precursors PSP-4-PVP·(AuCl/AgSOCF)·SiO 1:1 ( 1), PSP-4-PVP·(AuCl/AgSOCF)·SiO 1:5 ( 2), Chitosan·(AuCl/AgSOCF)·SiO 1:1 ( 3) and Chitosan·(AuCl/AgSOCF)·SiO 1:5 ( 4) were Au/Ag//SiO, Au//SiO and Ag//SiO as well as isolated Au and Ag, depending on the polymeric precursor. The Chitosan polymer precursor induces mainly Ag and Ag/SiO nanostructures, while PSP-4-PVP induces mainly Au/Ag//SiO nanostructures. This can be explained by the facility to link Ag to the NH and OH groups of Chitosan than to the pyridine of PSP-4-PVP. On the contrary, Au exhibits most coordination ability to pyridine groups of PSP-4-PVP than NH- and OH-groups of Chitosan. EDS mapping analysis indicates a uniform distribution of the Au/Ag nanostructure inside the SiO matrix. Using reflectance diffuse analysis, the plasmon is consistent with the Au/Ag alloys structure. [ABSTRACT FROM AUTHOR]

Graded anodes for anode-supported solid oxide fuel cells (SOFCs) are fabricated by tape casting and subsequent cold lamination of plates using different compositions. Rheological parameters are adjusted to obtain stable suspensions for tape casting. The conditions for the tape casting and lamination will be described. Flexural strength of the reduced cermets measured using three-point bending configuration is 468 ± 37 MPa. The graded anode supports are characterized by scanning electron microscope observations, mercury porosimetry intrusion, and resistivity measurements, showing an adequate and homogeneous distribution of nickel, zirconia, and pores. The laminated samples showed a total porosity of 18.7 % (in vol%) and a bimodal pore size distribution centered in 20 and 150 nm, and the measured electrical resistivity of this sample was 120 ± 12 μΩ cm. The novelty of the present work is the lamination of tapes at room temperature without using plasticizers. This is made by the combination of two different binders with varying T (glass transition temperature) which resulted in plastic deformation at room temperature. Those results indicate that the proposed process is a cost-effective method to fabricate anode-supported SOFCs. [ABSTRACT FROM AUTHOR]