Duan Guotao, Cai Weiping, Li Yue, Li Zhigang, Cao Bingqiang, Luo Yuanyuan
Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academia of Sciences, Hefei 230031, Anhui, P. R. China.
J Phys Chem B. 2006 Apr 13;110(14):7184-8. doi: 10.1021/jp057421t.
We report an electrochemical synthesis of two-dimensionally ordered porous Ni arrays based on polystyrene sphere (PS) colloidal monolayer. The morphology can be controlled from bowl-like to hollow sphere-like structure by changing deposition time under a constant current. Importantly, such ordered Ni arrays on a conducting substrate can be transferred integrally to any other desired substrates, especially onto an insulting substrate or curved surface. The magnetic measurements of the two-dimensional hollow sphere array show the coercivity values of 104 Oe for the applied field parallel to the film, and 87 Oe for the applied field perpendicular to the film, which is larger than those of bulk Ni and hollow Ni submicrometer-sized spheres. The formation of hollow sphere arrays is attributed to preferential nucleation on the interstitial sites between PS in the colloidal monolayer and substrate, and growth along PSs' surface. The transferability of the arrays originates from partial contact between the Ni hollow spheres and substrate. Such novel Ni ordered nanostructured arrays with transferability and high magnetic properties should be useful in applications such as data storage, catalysis, and magnetics.
我们报道了一种基于聚苯乙烯球（PS）胶体单层的二维有序多孔镍阵列的电化学合成方法。通过在恒定电流下改变沉积时间，其形貌可以从碗状控制为空心球状结构。重要的是，这种在导电基底上的有序镍阵列可以整体转移到任何其他所需的基底上，特别是转移到绝缘基底或曲面上。二维空心球阵列的磁性测量表明，对于平行于薄膜的外加磁场，矫顽力值为104 Oe，对于垂直于薄膜的外加磁场，矫顽力值为87 Oe，这比块状镍和亚微米尺寸的空心镍球的矫顽力值要大。空心球阵列的形成归因于在胶体单层中的PS与基底之间的间隙位置上的优先成核，以及沿着PS表面的生长。阵列的可转移性源于镍空心球与基底之间的部分接触。这种具有可转移性和高磁性的新型镍有序纳米结构阵列在数据存储、催化和磁性等应用中应该会很有用。
