(1. 蘭州理工大學(xué) 理學(xué)院，蘭州 730050；
2. 蘭州理工大學(xué) 甘肅省有色金屬新材料省部國家重點(diǎn)實(shí)驗(yàn)室， 蘭州730050；
3. 蘭州大學(xué) 物理科學(xué)與技術(shù)學(xué)院，蘭州 730000)
摘 要: 采用直流電弧等離子體技術(shù)制備NiO包覆Ni納米顆粒，對初產(chǎn)物經(jīng)過鈍化處理得到有氧化膜保護(hù)的NiO包覆Ni納米顆粒。采用高分辨透射電子顯微鏡(HRTEM)、X射線衍射(XRD)、透射電子顯微鏡(TEM)、選區(qū)電子衍射(SAED)、熱重和差示掃描量熱分析儀(TGA/DSC)以及傅里葉變換紅外光譜 (FTIR)等手段對試樣的成分、表面組成、形貌、晶體結(jié)構(gòu)、粒度、紅外吸收性能和氧化特性進(jìn)行了分析。結(jié)果表明：經(jīng)過表面鈍化處理的NiO包覆Ni納米顆粒具有明顯的核−殼結(jié)構(gòu)，內(nèi)核為納米Ni，外殼為NiO氧化物；顆粒呈球形，粒度均勻，分散性良好，粒徑分布在20~70 nm范圍，平均粒徑為44 nm，殼層氧化膜的厚度為5~8 nm；殼核結(jié)構(gòu)可防止納米Ni顆粒的進(jìn)一步氧化和團(tuán)聚，且使紅外吸收峰發(fā)生藍(lán)移。
關(guān)鍵字: NiO包覆；納米顆粒；核−殼結(jié)構(gòu)；鈍化；氧化特性
direct current arc plasma method
（1. School of Science, Lanzhou University of Technology, Lanzhou 730050, China;
2. State Key Laboratory of Gansu Advanced New Non-ferrous Materials, Lanzhou University of Technology,
Lanzhou 730050, China;
3. School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China）
Abstract:The NiO encapsulated Ni nanoparticles were prepared by direct current (DC) arc plasma method and subsequently passivation. The chemical composition, morphology, crystal microstructure, particle size, infrared spectra properties and oxidization resistance of the product were analyzed using the high-resolution transmission electron microscopy (HRTEM), X-ray diffractometry (XRD), transmission electron microscopy (TEM), corresponding selected-area electron diffractometry (SAED), thermogravimetric analyzer (TGA) differential scanning calorimeter (DSC) and Fourier transform infrared spectrum (FTIR). The results show that the NiO encapsulated Ni nanoparticles have clear core-shell structure. The core consists of Ni particles, while the shell consists of NiO. The samples are homogeneously distributed with spherical shape and well dispersed, the particle sizes distribute from 20 to 70 nm with average particle size of about 44 nm, and the thickness of the shell is 5−8 nm. The core-shell structure can prevent Ni nanopartictes from oxidation and agglomeration, and the infrared absorption band show blue-shifts.
Key words: NiO encapsulated; nanoparticles; core-shell structure; passivation; oxidization resistance
