【摘要】 以Fe和Y2O3的微米粉为原料,压制成块体靶材,利用物理气相蒸发法原位合成了核/壳型Fe/Y2O3纳米复合粒子,并对其成分、形态和微结构进行了研究。高分辨透射电镜和暗场成像分析结果表明Fe/Y2O3纳米复合粒子具有清晰的"核/壳"结构,其内核及外壳分别为-αFe和体心立方相Y2O3。通过"定量氧辅助-气-液-固"机制对纳米复合粒子的形成过程进行了探讨。实验结果表明,本文所采用的物理气相方法实现了稀土氧化物包覆异质金属纳米胶囊的合成,为多组元纳米结构的复合提供了实验依据。更多还原

【Abstract】 Fe/Y₂O₃ nanoparticles were in-situ synthesized by evaporating Fe-Y₂O₃ compact in a DC arc discharge chamber.The composition,morphologies and microstructures of the prepared nanoparticles were characterized by different analysis techniques.Fe/Y₂O₃ nanoparticles have a clear core-shell structure in the HRTEM bright-and dark-field images.The core is α-Fe,and the shell is body-centered-cubic Y₂O₃.The growth mechanism of "stoichiometric oxygen assistant vapor-liquid-solid" is proposed to explain the formation of particles.The experimental results indicate an effective route to combine iron and rare-earth oxides into a core-shell nanostructure,and provide a practical evidence for the synthesis and applications of such multi-component nanostructured composites.更多还原