20 documents found, page 1 of 2
Antimony-lead melts for high temperature electrochemical applications
Mikhalev, S. M.; Julião, Paulo S.B.; Loureiro, F. J.A.; Shaula, A. L.; Fagg, D. P.The electrochemical behaviour of antimony-lead melt on saturation with oxygen was studied to assess further prospects of such melts as anode materials for high-temperature fuel cells. A perovskite ceramic was used as a robust current collector material. The related mechanisms of alloying and phase segregation were revealed at different melt oxidation levels using combined impedance spectroscopy and thermodynami...
Antimony-lead melts for high temperature electrochemical applications
Mikhalev, S. M.; Julião, Paulo S.B.; Loureiro, F. J.A.; Shaula, A. L.; Fagg, D. P.The electrochemical behaviour of antimony-lead melt on saturation with oxygen was studied to assess further prospects of such melts as anode materials for high-temperature fuel cells. A perovskite ceramic was used as a robust current collector material. The related mechanisms of alloying and phase segregation were revealed at different melt oxidation levels using combined impedance spectroscopy and thermodynami...
Electrochemical assessment of novel misfit Ca-cobaltite-based composite SOFC ca...
Silva, V. D.; Silva, R. M.; Grilo, J. P .F.; Medeiros, E. S.; Loureiro, F. J. A.; Macedo, D. A.; Fagg, D. P.
Electrochemical assessment of Ca3Co4O9 nanofibres obtained by Solution Blow spi...
Silva, V. D.; Simões, T. A.; Loureiro, F. J. A.; Fagg, D. P.; Medeiros, E. S.; Macedo, D. A.
Structure, densification and electrical properties of Gd3+ and Cu2+ co-doped ce...
Santos, T. H.; Grilo, J. P. F.; Loureiro, F. J. A.; Fagg, D. P.; Fonseca, F. C.; Macedo, D. A.Ceria-based solid electrolytes exhibit superior electrical conductivity compared to traditional yttria-stabilized zirconia ceramics. However, they require high sintering temperatures to achieve full densification. Transition metal oxides exhibiting low melting points, such as CuO, have been used as additives to lower the sintering temperature of these materials. In this context, the present work is focused on t...
Chemically transformed additive phases in Mg2TiO4 and MgTiO3 loaded hydrogen st...
Pukazhselvan, D.; Nasani, N.; Yang, T.; Ramasamy, D.; Shaula, A.; Fagg, D. P.The present work deals with a comparative study of Mg2TiO4, MgTiO3 and titania additives incorporated MgH2. Hydrogen storage measurements suggest that all these additives improve the hydrogen desorption/absorption performance of MgH2. X-ray diffraction (XRD) and X ray photoelectron spectroscopy (XPS) studies highlight that rock salt phases consisting of highly reduced Ti exist in the samples. These results reit...
Thermal evolution of structures and conductivity of Pr-substituted BaZr0.7Ce0.2...
Heras-Juaristi, G.; Amador, U.; Fuentes, R. O.; Chinelatto, A. L.; De Paz, J.Romero; Ritter, C.; Fagg, D. P.; Pérez-Coll, D.; Mather, Glenn C.A complete solid solution forms between the perovskite proton conductor BaZr0.7Ce0.2Y0.1O3-δ (BZCY72) and BaPr0.9Y0.1O3-δ (BPY) on synthesis by the Pechini method and high-temperature annealing. Phase fields of selected members of the Ba(Zr0.7Ce0.2)1-(x/0.9)PrxY0.1O3-δ series were studied as a function of composition and temperature by high-resolution neutron powder diffraction revealing symmetry changes in the...
Structure and Electrical-Transport Relations in Ba(Zr,Pr)O3-d Perovskites
Antunes, I.; Amador, U.; Alves, A.; Correia, M. R.; Ritter, C.; Frade, J. R.; Pérez-Coll, D.; Mather, G. C.; Fagg, D. P.Members of the perovskite solid solution BaZr1−xPrxO3−δ (0.2 ≤ x ≤ 0.8) with potential high-temperature electrochemical applications were synthesized via mechanical activation and high-temperature annealing at 1250 °C. Structural properties were examined by Rietveld analysis of neutron powder diffraction and Raman spectroscopy at room temperature, indicating rhombohedral symmetry (space group R3̅c) for members ...
Exploring the effects of silica and zirconia additives on electrical and redox ...
Ferreira, N. M.; Ferro, M. C.; Fagg, D. P.; Costa, F. M.; Frade, J. R.; Kovalevsky, A. V.The interplay of unique cation arrangement and redox coupling in ferrospinels offers a wide range of magnetic and catalytic properties, evaluated mostly for low and intermediate temperature applications. This work focuses on high-temperature properties of magnesium-substituted magnetite, for prospective high temperature applications such as electrodes for pyroelectrolysis, energy conversion, catalysis, etc. The...
Electrochemical assessment of one-step Cu-CGO cermets under hydrogen and biogas...
Sousa, A. R. O.; Araujo, A. J. M.; Souza, G. S.; Grilo, J. P. F.; Loureiro, F. J.; Fagg, D. P.; Macedo, D. A.CuO-Ce0.9Gd0.1O1.95 (CuO-CGO) nanocomposite powders obtained by in situ one-step synthesis were used to prepare Cu-CGO cermet anodes for solid oxide fuel cells (SOFCs). The effects of the CuO content (varying from 40 to 60 wt.%) on the lattice parameter and crystallite size of CuO and CGO phases were investigated by X-ray diffraction (XRD) with Rietveld refinement of the XRD data. CuO-CGO composites were screen...