Optimizing the structure of Ni–Ni(OH)2/NiO core-shell nanowire electrodes for application in pseudocapacitors: The influence of metallic core, Ni(OH)2/NiO ratio and nanowire length

An experimental analysis was performed to optimize the structure of Ni–Ni(OH)2/NiO core-shell nanowire electrodes for improving their application in pseudocapacitors. Thickness and composition active phase shell were compared after thermal treatments at 40, 70 300 °C. A Ni(0) core found by XPS electrode treated 40 °C, it still present a temperature increase °C but with lower Ni(OH)2/NiO ratio shell, disappeared annealing corresponding charge transfer resistance. The capacitance values increased from drop minimum tailoring controlling length evaluated. constant per nanowires unit attained between 5 21 ?m, indicating that mass resistance negligible over explored range. These results evidence relevance tightly control thickness Ni(OH)2 NiO provide guideline length.