arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1111.5416cond-mat.mtrl-sciphysics.chem-ph
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碳纳米管的电子和磁性结构的X射线吸收和磁性圆二色谱研究

Electronic and magnetic structure of carbon nanotubes using x-ray absorption and magnetic circular dichroism spectroscopy

Sanjeev Gautama, P. Thakur, S. Augustine, J. K. Kang, J. -Y. Kim, N. B. Brookes, K. Asokan, Keun Hwa Chae

摘要:

碳纳米管的尺寸只是当今最好的微芯片中使用的晶体管的一小部分,因为它可以减少下一次电子革命中的电力需求和发热。利用近边X射线吸收光谱(NEXAFS)和X射线磁性圆二色性(XMCD)分别对化学气相沉积法合成的多壁碳纳米管(MWCNT)的C K边和Co、Fe $L_{3,2}$边进行了电子结构和磁性研究。在C K边的NEXAFS显示出明显的$π$ -键合,Fe(Co)L边证明了Co $^{2+}$和Fe $^{2+}$以八面体对称的形式存在,并嵌在碳纳米管的C-基体中.元素特异性磁滞回线和XMCD谱清楚地表明,这些MWCNTs表现出室温铁磁性。这些测量阐明了CNT的电子结构和在室温下的磁相互作用的存在。

英文摘要:

Carbon nanotubes are a fraction of the size of transistors used in today's best microchips, as it could reduce power demands and heating in next electronics revolution. Present study investigates the electronic and magnetic structure of multi walled carbon nanotubes (MWCNT) synthesized by chemical vapor deposition technique using near edge x-ray absorption spectroscopy (NEXAFS) measurement at C K-edge and x-ray magnetic circular dichroism (XMCD) at Co and Fe $L_{3,2}$ -edges. NEXAFS at C K-edge shows significant $π$-bonding, and Fe(Co) L-edge proves the presence of Co$^{2+}$ and Fe$^{2+}$ in octahedral symmetry, and embedded in C-matrix of MWCNT. Element specific hystersis loops and XMCD spectra clearly shows that these MWCNTs exhibits room temperature ferromagnetism. These measurements elucidated the electronic structure of CNTs and presence of magnetic interactions at room temperature.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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