超细镍粉的化学还原制备及其分散剂的作用

Synthesis of ultrafine nickel powder by solution reduction technique and effect of the dispersant

采用溶液还原法，以硫酸镍为原料，水合肼为还原剂制备了超细和纳米镍粉。研究了不同分散剂对镍粉粒度和粒度分布的影响。X射线衍射结果表明，所得粉末为纯Ni相，晶粒尺寸约13nm；激光粒度分布测试结果表明，Ni粉粒度分布较窄，中位径集中在0．7～0．8μm，最大粒径不超过2．0μm。透射电镜照片显示粉末近球形，一次颗粒粒径在50～100nm之间，有轻微团聚。改变分散剂种类（PVP、PEG1500、PEG20000、CTAC）和用量可使超细镍粉的比表面积在3．24～57．88m^2／g间变化。

Ultrafine and nanosized nickel powder was synthesized in a solution containing NiSO4· 6H2O and N2H4·H2O. Various kinds of dispersants were added to the solution to investigate their effect on the nickel powder particle size and particle size distribution. X-ray measurement shows that the synthesized powder consists of pure nickel phase with grain size of about 13nm. Laser particle size determination shows the resultant nickel powder has a narrow particle size distribution with maximum particle size less than 2.0μm and D50 is in the range of 0.7 - 0.8μm. Transmission electron microscopy determination shows the nickel powder is of spheric shape with grain size ranged from 50 - 100nm and has slight agglomeration. The specific surface area of the nickel powder can be altered from 3.24- 57.88m^2/g by changing kind and amount of the dispersant PVP.PEG1500.PEG20000 or CTAC.