Solid oxide fuel cells are highly efficient energy conversion devices which convert fuels electrochemically to electricity with negligible pollution emissions. Anode of solid oxide fuel cell plays an important role in converting hydrogen into hydrogen ions and electrons. Many techniques like plasma spraying, tape casting, screen printing, sintering process etc have been discovered for the fabrication of anode supported solid oxide fuel cells. In order to meet the high demand of energy in present days a new technique is required for increasing the efficiency. Among the various methods, increasing porosity of anode is one. This can be achieved by fabricating the anode by electrodeposition technique, which has been proved as an effective way of increasing porosity. In this work, we demonstrated that nanoporous Ni can be electroplated on a Zr substrate.
Electrochemical dealloying of copper from a Ni-Cu alloy wire is carried out first to better understand the effect of voltage and run time on the process. As the potential increases the amount of copper dealloyed in to the solution was also increased. Passivation of nickel occurs as the time increases, allowing the formation of NiO. The preparation of nanoporous nickel films on zirconium by electrochemical deposition of Ni-Cu alloy followed by selective anodic etching of the more noble metal, copper, was studied in an aqueous solution containing Ni and Cu at room temperature. Variable potential electrodeposition produces crystalline or grain Ni-Cu alloys on Zr substrate, in which the Ni content increases as the deposition potential becomes more negative.
Cyclic voltammetric data indicates that the anodic dissolution of nickel is retarded by passivation. By taking the advantage of nickel passivation, selective anodic etching of Cu is carried out. Multicyclic electrochemical alloying/dealloying process makes the film rich of nickel and complete dealloying of copper.