Recently , as an advanced and eco - friendly method of powder preparation , freeze - drying has been developing quickly . the ultrafine ni powder with the average size of 50nm was prepared by freeze - drying form the niso4 and naoh and was studied by means of xrd , ir , fesem , tem , and dsc . the catalysis of nickel powders to nh4clo4 and how the precursor forms and the processes of the amorphous precursor to the final nickel powders are discussed 本論文以分析純niso4 、 naoh為原料,采用冷凍干燥技術(shù)成功的制備了50nm左右的球狀超細(xì)鎳粉,通過xrd 、 ir 、 fesem 、 tem 、 dsc等材料現(xiàn)代分析手段對(duì)產(chǎn)物進(jìn)行了分析和表征,研究了超細(xì)鎳粉對(duì)高氯酸銨熱分解的催化活性、前驅(qū)體的形成以及非晶態(tài)金屬鹽到晶態(tài)超細(xì)鎳粉的轉(zhuǎn)變過程。