Document Type : Research Paper
Iranian Research Organization for science and Technology
Department of Chemical Technologies, Iranian Research Organization for Science and Technology (IROST)
University of Tehran- School of Metallurgy and Materials Engineering
In this study, nickel oxide-gadolinium doped ceria, NiO–GDC, composite powder was synthesized by the sol-gel method with a new Ni(II) complex. New Ni(II) complex with the chemical formula [Ni(μ-L)]n(NO3)2, L = N’-(pyridine-2-yl)methylene)isonicotinohydrazide), have been used as a new precursor. The new Ni(II) complex has been prepared by the reaction between ligand, L, and Ni(NO3).6H2O by hydrothermal method. Then the NiO–GDC powders have been synthesized by Ce(NO3)3.6H2O and Gd(NO3) 3.6H2O and as-synthesized new Ni(II) complex, [Ni(μ-L)]n(NO3)2 by sol-gel method. To increase the performance of solid oxide fuel cells (SOFCs) operating at intermediate temperatures (600–800 ℃), by increasing the three-phase boundary region in the anode, the NiO-GDC powder was modified. The NiO–GDC anode powders as prepared by new precursor has been compared with the NiO-GDC anode powders that has been synthesized from metal nitrates as a precursor. The results showed that the modified NiO-GDC anode has more three-phase boundaries, TPB, a more uniform microstructure, a higher specific surface area, and a porous structure that effectively improved the electrochemical performance of the electrode. The resistance of half-cells of SOFC with this high-performance anode decreased by 85 % at 800 ℃ when compared to conventional half-cells.