Studies On Ni Nanowires Array Electrodeposited In PAA Template From A Ionic Liquid

The electrodeposition of Ni from EMIC-NiCl2 ionic liquid was investigated. The addition of acetonitrile, glycol (EG) and glycerin increased the electrolyte conductivity apparently. Simultaneously, glycol can enhance the quality of the deposit. By considering the effect of additional content of glycol, additive, current density, temperature on deposit quality, the optimal electrolyte composition and operating conditions are: the molar ratio of EMIC-NiCl2-EG 2:1:6~2:1:9; 2-butyne-1,4-diol 0.2~0.4 g·L-1; current density 50~80A·m-2; temperature 80~100℃. Under these conditions, FE-SEM indicated that the appearance of Ni plating is pretty wonderful. XRD analysis indicated that the addition of glycol in electrolyte can change the crystal orientation of Ni, and the grains preferred to grow at the plateau of (220); contrarily, when 2-butyne-1,4-diol was added into EMIC-NiCl2-EG electrolyte.And the width of diffraction peaks for Ni is increased.By cathodic polarization curves and chronoamperometric methods, the deposition mechanism of metallic Ni from ionic liquid was also discussed preliminary. The results indicated that the electrodeposition of Ni at electrode belonged to a three-dimensional instantaneous nucleation mechanism. PAA film was used as template to prepare Ni nanowires from ionic liquid by DC method. TEM and FE-SEM analysis indicated that the nanowires deposited from ionic liquid is uniform. Hysteresis loops results indicated that square ratio deposited from ionic liquid in PAA of sulfuric acid is 0.72, coercivity is 646Oe; square ratio deposited from oxalic liquid in PAA of sulfuric acid is 0.36, coercivity is 522Oe. the magnetic recording property is apparently better than that of nanowires deposited from oxalic acid. Nanowire had strong perpendicular magnetic anisotropy.