惰性气体冷凝法制备镁纳米颗粒的工艺及机制

以纯度为99.9%的镁粉为原料,采用惰性气体冷凝法来制备镁纳米颗粒,研究了蒸发温度及沉积位置对镁纳米颗粒形貌和尺寸的影响。结果表明,蒸发温度为600℃时,在冷阱最前端得到了直径为10~50 nm的镁纳米颗粒,纳米颗粒之间相互连接呈链状形态,并且在镁纳米颗粒之间发现了镁纳米线。结果还表明,随着蒸发温度升高,得到的镁纳米颗粒尺寸增大;随着沉积位置的变化,其镁纳米颗粒尺寸也发生规律性变化。根据气/固相变理论及机制,对镁纳米颗粒的形成过程进行了解释,提出了相应的镁纳米颗粒的形成模型。

Preparation of Mg Nanoparticles by Inert Gas Condensation and Its Mechanism

Mg nanoparticles were prepared by an inert gas condensation method using magnesium powder of 99.9% purity, and the effect of evaporating temperature and deposition location on the morphology and size of Mg nanoparticles were studied. Result shows that chain-like Mg nanoparticles with size of 10~50 nm are prepared in the front tip of the cold trap at the evaporation temperature of 600 oC. Some Mg nanowires are observed among the nanoparticles. Smaller size Mg nanoparticles are obtained at lower evaporation temperature in the front and back tips of the cold trap. According to collision and coagulation mechanism in the gas-solid phase transition theory, the formation process of Mg nanoparticles was explained and the corresponding model was established.