Fabrication and magnetic properties of Ni nanowire arrays with ultrahigh axial squareness

Poly- and single-crystalline Ni nanowire arrays showing ultrahigh axial squareness are fabricated by direct-current electrodeposition in pores of anodic aluminum oxide templates. High voltage is shown to be the key in order for Ni nanowires to have a (220) preferred orientation. 2-Dimensional nucleation theory is used to understand the growth of the nanowires. Based on the structure and growth analyses, the magnetic properties of different kinds of nanowires are explained. Poly- and single-crystalline Ni nanowire arrays showing ultrahigh axial squareness are fabricated by direct-current electrodeposition in pores of anodic aluminum oxide templates.