聚合物模板辅助镍微球的水热制备

以三嵌段共聚物HO(CH₂CH₂O)₂₀(CH₂CH(CH₃)O)₇₀(CH₂CH₂O)₂₀H (P123)为模板剂, 次亚磷酸钠为还原剂, 水热制备了微米级镍微球. 采用X射线衍射(XRD)、扫描电镜(SEM)和振动样品磁强计(VSM)对产物进行表征. 结果表明, 镍微球由纳米级的镍微晶组成, 其中至少部分微球存在空心结构. 微球的尺寸随着前驱体溶液pH值的增加而减小, 其聚集成链的程度随着水热温度的上升而增强. 120和220 ℃水热合成微球的直径范围、平均微晶尺寸和矫顽力分别是1.5～4.5和0.8～4.5 μm, 16.0和14.2 nm, 以及91.5和66.1 Oe.

Nickel Microspheres Prepared by Hydrothermal Process Assisted with Polymer Template

Nickel microspheres have been prepared by a hydrothermal process with a template of triblock copolymer HO(CH₂CH₂O)₂₀(CH₂CH(CH₃)O)₇₀(CH₂CH₂O)₂₀H (P123) and a reductant of sodium hy-pophosphite. The prepared products were characterized with X-ray diffraction (XRD), scanning electron mi-croscopy (SEM) and vibrating sample magnetometer (VSM). Results show that the nickel microspheres are composed of nickel nanocrystals, and at least a part of them possess hollow structures. The size of the mi-crospheres decreases with an increase in pH value of the precursor solution, and their aggregation degree to form chainlike assemblies rises with the elevation of temperature. Two kinds of microspheres prepared at 120 and 220 ℃ have diameter ranges of 1.5～4.5 and 0.8～4.5 μm, and consist of nanocrystals with aver-age sizes of 16.0 and 14.2 nm, and their coercivities are 91.5 and 66.1 Oe, respectively.