Growth of copper nanowire arrays on NiTi shape memory alloy thin film

Copper nanowire arrays were synthesized on NiTi shape memory alloy thin films to improve thermal actuation. To grow the forest of Cu nanowires, an Al film was deposited on top of the NiTi by DC sputtering, anodized in oxalic acid to form anodic aluminum oxide (AAO), and then the copper was electrodeposited inside the nanochannels of the template. Growth of these Cu nanowires was studied by electrochemical methods: anodization and electrodeposition rates were characterized using current density versus time diagrams. The morphology and crystal structure of Cu nanowires were evaluated by field emission scanning electron microscopy and X-ray diffraction.