碳包覆NiO纳米颗粒的制备与性能

Preparation and characterization of carbon-encapsulated NiO nano particles

采用直流电弧放电等离子体技术成功制备了碳包覆NiO(NiO@C)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、X射线衍射、X射线能量色散分析谱仪、拉曼散射光谱和N_2吸-脱附等测试手段进行了分析。实验结果表明:直流电弧等离子体技术制备的NiO@C纳米颗粒具有典型的核壳结构,内核为面心立方结构的NiO纳米颗粒,外壳为碳层。颗粒形貌主要为立方体结构,粒度均匀,分散性良好,粒径分布在30~70nm范围,平均粒径为50nm,外壳碳层的厚度为5nm。NiO@C纳米颗粒BET比表面积为28m^2/g,等效直径为46nm,与TEM和XRD测得的结果基本一致。Raman光谱说明样品中碳包覆层的石墨化程度较低,发生了红移现象。

Carbon encapsulated NiO（NiO@C）nano particles were successfully prepared by DC arc discharging plasma technology. The product is characterized by HRTEM, XRD, X-ray energy dispersive spectrometry （XEDS）,Raman spectroscopy and low-temperature N2 adsorption desorption to determine the morphology,crystal structure,particle size,specific area and pore structure.The experimental results indicate that the NiO@C nano-particles prepared by DC arc plasma technology possess typical core shell structure,the core of the particles is NiO with face centered cubic structure,and the outer shell is disordered carbon layer.The particle morphology exhibits cube structure with uniform particle size and good dispersion.The particle size distribution is in the range of 30-70 nm,the average particle size is 50 nm,and the thickness of the carbon shell is about 5 nm.The BET specific surface area of the carbon encapsulated NiO nano particles is 28 m2/g,and the equivalent particle size is 46 nm, which is consistent with the results measured by HRTEM and XRD.Raman spectrum shows that the degree of graphite in the sample is low,and the red shift phenomenon occurs.