【作者】 孙舰鹏；

【导师】 董星龙；

【作者基本信息】 大连理工大学 ， 材料物理与化学， 2007， 硕士

【摘要】 随着纳米技术的发展，包含2种或2种以上纳米尺度功能材料的纳米复合粒子已经成为当前材料学中一个越来越活跃的研究方向，磁性核壳纳米复合粒子正是其中之一。由于氢能源具有效率高、污染小等优点，将逐步取代化石燃料而成为将来主要的能源形式。氢能源使用过程中一个关键的环节是找到一个很好的储存氢的方式。本文采用直流电弧等离子体法以磁性金属和氧化物的微米粉为原料，成功制备了Ni／MnO，Ni／TiO₂，Fe-MnO₂，Fe-TiO₂纳米复合粉体，通过XRD，TEM，和红外分析检测方法，确定了这四种纳米复合粒子都是核壳结构纳米粒子。热分析说明Ni／MnO和Fe-MnO₂的氧化物外壳极大的提高了内核金属的氧化温度。根据定量氧辅助V-L-S机制，金属核在复合粒子生长的过程中起到的催化作用，是核壳结构形成的重要因素。并通过对电磁参数的分析发现不同的氧化物外壳，对纳米复合粒子的电磁性能有特殊的影响，外壳氧化物含量的增加，降低了粉体的电磁参数。本文中对直流电弧法制备的Mg-Cu合金纳米粒子进行了分析。XRD的结果说明改变原料的配比，对产物的影响不大。结合热力学原理说明了Mg-Cu合金纳米粒子的形成规律。在对Mg-Cu合金纳米粒子进行储氢性能测试过程中，发现直流电弧法制备的Mg-Cu合金纳米粒子在经过一次活化后就有良好的储氢性能。Mg-Cu合金纳米粒子在623K、598K、573K下最大吸氢量分别为2.05 wt％、1.97wt％、1.90wt％。更多还原

【Abstract】 With the development of nano-technology, nanocompsite particles which contain two or more nano-scale functional materials are an active study field of material. Magnetism core/shell nanocompsite particles are one of that. Hydrogen energy will surely take the place of fossil fuels as the new energy source in the future due to its advantages, such as high efficiency and low price. Hydrogen storage is the key problem in practical applications.In this article, Ni/MnO, Ni/TiO₂, Fe-MnO₂ and Fe-TiO₂ nanocompsite particles are prepared by the arc-discharge method using magnetism metals and oxides as the raw materials. Four nanocompsite particles are core/shell structure nanoparticles proved by XRD, TEM and FT-IR. The thermal analysis shows Ni/MnO and Fe-MnO₂ nanocompsite particles can improve the oxidation temperature of the core metals. The formation of nanoparticles was effectively explained by an extended mechanism of the Vapor-Liquid-Solid （VLS） with the existence of stoichiometric oxygen. The metal core plays an essential catalyst in the formation of the core/shell structure. The results of electromagnetism parameter analysis show that the different oxide shells have special effect to the electromagnetism parameter of the nanocompsite particles. Otherwise, the electromagnetism parameters of the nanocompsite particles decrease with increase of oxide shell.Mg-Cu alloy nanoparticles prepared by arc-discharge method are analyzed in this article. The results of XRD shows, the production is hardly affected by changing the proportion of the raw material. The formation rule of Mg-Cu alloy nanoparticles is illustrated according to thermodynamics. The Mg-Cu alloy nanoparticles have well hydrogen absorption properties after one time activation, during the test of hydrogen absorption capability of Mg-Cu alloy nanoparticles. The maximize of hydrogen absorption of Mg-Cu alloy nanoparticles is 2.05 wt%,1.97 wt% and 1.90 wt% at 623K,598K and 573K.更多还原