Wang Dongxing, Li Da, Muhammad Javid, Zhou Yuanliang, Wang Ziming, Lu Sansan, Dong Xinglong, Zhang Zhidong
Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Materials Science and Engineering, Dalian University of Technology Dalian 116023 China
Shenyang National Laboratory for Materials Science, Institute of Metal Research, International Center for Materials Physics, Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 People's Republic of China
RSC Adv. 2018 Feb 15;8(14):7450-7456. doi: 10.1039/c8ra00078f. eCollection 2018 Feb 14.
A nanocomposite of Ag@C nanocapsules dispersed in a multi-walled carbon nanotube (MWCNT) matrix was fabricated by a facile arc-discharge plasma approach, using bulk Ag as the raw target and methane gas as the carbon source. It was found that the Ag@C nanocapsules were ∼10 nm in mean diameter, and the MWCNTs had 17-32 graphite layers in the wall with a thickness of 7-10 nm, while a small quantity of spherical carbon cages (giant fullerenes) were also involved with approximately 20-30 layers of the graphite shell. Typical dielectric behavior was dominant in the electronic transport of Ag@C/MWCNT nanocomposites; however, this was greatly modified by metallic Ag cores with respect to pure MWCNTs. A temperature-dependent resistance and - relationship provided evidence of a transition from Mott-David variable range hopping [ln () ∼ ] to Shklovskii-Efros variable range hopping [ln () ∼ ] at 5.4 K. A Coulomb gap, ≈ 0.05 meV, was obtained for the Ag@C/MWCNT nanocomposite system.
采用简便的电弧放电等离子体方法，以块状银为原始靶材、甲烷气体为碳源，制备了分散在多壁碳纳米管（MWCNT）基质中的Ag@C纳米胶囊纳米复合材料。研究发现，Ag@C纳米胶囊的平均直径约为10 nm，MWCNT的管壁有17 - 32层石墨层，厚度为7 - 10 nm，同时还包含少量具有约20 - 30层石墨壳的球形碳笼（巨型富勒烯）。典型的介电行为在Ag@C/MWCNT纳米复合材料的电子输运中占主导地位；然而，相对于纯MWCNT，金属Ag核使其发生了很大改变。电阻与温度的关系表明，在5.4 K时发生了从莫特 - 戴维可变程跳跃[ln( ) ∼ ]到什克洛夫斯基 - 叶夫罗夫可变程跳跃[ln( ) ∼ ]的转变。Ag@C/MWCNT纳米复合材料系统获得了约0.05 meV的库仑能隙。
