Ni纳米线阵列的电化学组装及磁性能研究

利用二次氧化法制备了多孔阳极氧化铝(AAO)模板,通过恒电位沉积法在模板内组装了Ni纳米线阵列。采用SEM、TEM、SAED、EDS和VSM等检测技术对填孔过程、阵列形貌、结构和磁性能进行了分析和表征。结果表明,Ni纳米线在纳米孔中的生长过程经历四个阶段,填孔终止时间控制在第三阶段。适宜AAO模板中Ni纳米线沉积的电位为-0.9 V,pH为3.5。Ni纳米线是沿着(111)方向生长的单晶结构。当外磁场平行或垂直Ni纳米线阵列时,在磁场强度周期变化下,测量纳米线阵列磁滞现象的闭合磁化曲线,Ni纳米线阵列在平行和垂直两个方向的磁性不同,剩余磁化强度Mr与饱和磁化强度Ms之比分别为0.282和0.055,其矫顽力是293 Oe、100 Oe。

Study on Electrochemical Assembly of the Nanowire Array and Its Magnetic Properties

A porous anodized aluminum oxide (AAO)template was prepared by secondary oxidation method,and nickel nanowire arrays were assembled in the template by DC constant potential deposition.Filling process,morphology,structure and magnetic properties of the arrays were analyzed by means of SEM,TEM,SAED,EDS and VSM.Results showed that the growth process of the nickel nanowires in nanopores underwent four stages,and the filling completing time was controlled in the third stage.The suitable potential of the nickel nanowire deposition in AAO template was-0.9 V,and the pH value was 3.5.The nickel nanowire is a single crystal structure which grew along (111) direction.When the external magnetic field was parallel or perpendicular to the nanowire array,the closed magnetization curve of magnetic hysteresis of the nanowire array was measured under the magnetic field periodically changed condition,the nickel nanowire arrays were of different magnetic properties in parallel and perpendicular directions,the ratio of the residual magnetization intensity (Mr) to the saturation magnetization (Ms) was 0.282 and 0.055 respectively and its coercive force was 293 Oe and 100 Oe.