Synthesis of nickel oxide/gadulinium doped ceria nanostructures by new methods as anode material for solid oxide fuel cells: Ni(II) complexes as new precursors

Nickel oxide/gadolinium dopped ceria nano powders, NiO/GDC, (NGC) with controlled morphology were synthesized by the sol-gel method. The nickel(II) coordination compounds have been used as new precursors for the preparation of ceramic materials, NiO/GDC, as anodic powders for application in solid oxide fuel cells. The formation of diverse morphologies with different porosity was observed by varying the Nickel(II) coordination compounds, [NiL^2(μ-acetylenedicarboxylate)]n, [NiL^2(μ-terephthalate)] n and [NiL^2(μ-2,6 pyridinedicarboxylate)]n. Then three different kinds of nickel oxide / gadolinium dopped ceria, namely NGC (a), NGC (b), and NGC (c) samples, each of a different shape, were developed by new precursors. These powders have been used as electrocatalysts for solid oxide fuel cells. The catalytic performance of NGC anodes for the hydrogen oxidation reaction was analyzed via impedance spectra test using yttria-stabilized zirconia (YSZ)-supported symmetry half-cell. The modified NGC (c) anode powder fabricated with the new precursor of [NiL^2(μ-2,6 pyridinedicarboxylate)] n (N’-(pyridine-3-yl)methylene)isonicotinohydrazide (L)) manifested the least polarization resistivity of 0.106 Ω. cm^2 measured at 800 under humidified H2. The NGC (c) anode powder with a better pore distribution and excellent microstructure demonstrated the most desirable electro-catalytic activity.