【摘要】 采用直流电弧放电等离子体技术成功制备了碳包覆氧化亚钴纳米颗粒,并对样品的形貌、晶体结构、粒度、比表面积和孔结构采用高分辨透射电子显微镜（HRTEM）、X射线衍射（XRD）、X射线能量色散光谱（XEDS）、拉曼散射光谱（Raman）和N₂吸-脱附等测试手段进行了分析。HRTEM表明该方法制备的碳包覆氧化亚钴纳米颗粒具有典型的核壳结构,颗粒形貌主要为球形或椭球结构,粒度均匀,分散性良好,粒径分布在20⁶0nm,平均粒径为40nm,外壳碳层的厚度为5nm。XRD证明样品的内核为面心立方结构的氧化亚钴纳米颗粒,外壳为碳层。XEDS图谱表明样品中主要存在Co、O和C元素的特征峰。Raman光谱说明样品中碳外包覆层的石墨化程度较低,发生了红移现象。样品的N₂吸附-脱附等温曲线属Ⅳ型,BET比表面积为33m²/g,BJH脱附累积总孔孔容和脱附平均孔径分别为0.078cm³/g和11nm。当量粒径为43nm,与TEM和XRD测得的结果基本一致。更多还原

【Abstract】 Carbon-encapsulated CoO core-shell structure nanoparticles were successfully prepared by DC arc discharge plasma technique.The product was characterized by high resolution transmission electron microscopy（HRTEM）,X-ray diffraction（XRD）,and X-ray energy dispersive spectrometry（XEDS）.Raman spectroscopy and low-temperature N₂ adsorption/desorption were employed to determine the morphology,crystal structure,specific area,and pore structure of the nanoparticles.HRTEM indicated that the carbon-encapsulated CoO nanoparticles prepared by this method possess typical core shell structure.The particle morphology exhibits spherical or ellipsoidal structure with uniform particle size and good dispersion.The particle size distribution is in the range of 20—60 nm,the average particle size is 40 nm,and the thickness of the shell carbon layer is about 5 nm.XRD studies demonstrate that the core of the particles is CoO with face-centered cubic structure CoO,and the outer shell is disordered carbon layer.XEDS spectra confirmed the presence of Co,O and C elements in the sample.Raman spectrum showed the low degree of graphite in the sample and the occurrence of red shift phenomenon.The N₂ adsorption and desorption isotherm belongs to typeⅣ,the BET specific surface area is 33 m²/g,the BJH desorption cumulative pore volume and desorption average pore size are 0.078 cm³/g and 11 nm,respectively.The equivalent particle size is 43 nm,which is consistent with the results measured by TEM and XRD.更多还原