FeSO4水溶液超薄液层电沉积物的形貌选择及其磁性研究

利用FeSO4水溶液进行超薄液层电沉积实验研究,重点考察沉积物的形貌选择及其磁性特征。在较大的沉积电流条件下,可获得纳米量级厚度的纤维状电沉积物;而在较小的沉积电流条件下,获得的薄膜状电沉积物的厚度达到了亚微米量级。在此基础上,利用磁力显微镜检测具有不同形貌的Fe的电沉积物经自发磁化以及经不同外加恒稳磁场磁化后所形成的表面杂散磁场分布,以此推断磁畴在样品中的分布规律。最后,利用交变梯度磁强计检测所得电沉积物的磁性特征,所得实验结果表明样品的易磁化轴位于电沉积物生长所在平面,不同方向饱和磁化强度的大小取决于样品的生长方向、几何尺寸及其形貌特征。

Pattern Selection and the Magnetic Property of Electrodeposits Grown within a Ultrathin FeSO4 Solution Layer

The unique ultrathin electrolyte layer deposition process is helpful for the investigation of the pattern formation and the pattern selection of metal and metal oxides with the micro-nanometer scale. Under different growth driving force, the electrodeposits will present the different patterns. Moreover, the distribution of magnetic domains formed in the magnetic metals, for instance the micro-nanometer Co filaments obtained through the ultrathin electrolyte layer electrodeposition process, will be affected by their geometry such as the thickness and the width remarkbely. In this paper, through the ultrathin FeSO<sub>4</sub> solution layer electrodeposition process, the iron electrodeposits with the filament or the film like morphology grown under the different electrodeposition currents were obtained. Compared with the Fe filaments with nanometer thickness formed under the higher electrodeposition current, the film like electrodeposit formed under the lower electrodeposition current presented the sub-micron thickness. Further, based on the magnetic force microscopy (MFM), we measured the distribution of the stray magnetic field around the electrodeposits with different morphology, which is resulted from the magnetic domains formed in the electrodeposits through the self-assembled process or the magnetization process under applied static magnetic field. Finally, the magnetic property of samples were measured with the alternating gradient magnetometer (AGM), the obtained hysteresis loops presented that the ease axis is located in the plane of the electrodeposits growth, and the saturation magnetization at different directions should be determined by the growth direction, the geometry, and the morphological characteristics of electrodeposits.