纳米Ni、Ni-P、Ni-B粒子制备及催化AP热分解的研究

Synthesis of Ni,Ni-P and Ni-B nanoparticles and their catalytic effect on the thermal decomposition of ammonium perchlorate

采用改进的化学镀镍方法，制备了纯度较高的纳米Ni、Ni-P及Ni-B粒子。运用透射电子显微镜（TEM）和X-ray射线衍射（XRD）方法对纳米粒子的物相、组织形貌和粒度进行了表征，并通过TG-DTA热分析实验，研究了制备的纳米粒子对AP热分解过程的催化影响。结果表明，纳米Ni粒子为面心立方晶体，呈现球形且平均粒径为60nm左右；纳米Ni-P、Ni-B粒子为非晶合金，粒子呈现松散的聚集状态，形状不规则，粒径分布分别为10-80nm和30-50nm。制备的纳米粒子对AP低温和高温热分解反应均有促进作用，对高温分解的催化效果更明显，而Ni-B粒子的催化效果最为显著。加入质量分数为5％的Ni或Ni-P粒子，能将AP的高温热分解峰温分别降低53℃或80℃左右；而加入质量分数为5％的Ni-B粒子，能将AP的高温热分解峰提前125℃左右，与其在321．68℃的低温热分解峰重合，并使得整体热分解在368．33℃时就完全结束。

Crystalline Ni, amorphous Ni-P and Ni-B nanoparticles with high purity were prepared by using a modified electroless plating method. The resulting samples were characterized by transmission electron microscope（ TEM）, X-ray diffraction（XRD） and the catalytic effect of the prepared nanoparticles on the decomposition of ammonium perchlorate was investigated using TG- DTA. The results indicate that Ni nanoparticles are in spherical shape with average size of about 60 nm in cubic crystal structure ; Ni-P and Ni-B nanoparticles are an aggregation of ultrafine alloy particles with relatively wide size distribution of 10 - 80 nm and 30 - 50 nm respectively in amorphous structure. Ni, Ni-P and Ni-B nanoparticles have significant catalytic effect on thermal decomposition of AP, the effects are more apparent on the stage of high-temperature decomposition, and Ni-B nanoparticles have the greastest influence on the high-temterature decomposition of AP among the resulting nanoparticles. Compared with pure AP, adding Ni or Ni-P nanoparticles （5%） in AP resulted in a decrease of peak temperature of high-temperature decomposition of about 53 ℃ or 80 ℃ ; however adding Ni-B nanoparticles （5%） in AP resulted in more significant reduction of peak temperature of high-temperature decomposition from 457.37 ℃ to 321.68 ℃ i.e. about 125 ℃ and disappearance of the peak of high temperature decomposition, which leads that the whole thermal decomposition stage shows one single exothermic peak at 321.68 ℃ and ends at 368.33 ℃.