Kitaygorodskiy Alex, Wang Wei, Xie Su-Yuan, Lin Yi, Shiral Fernando K A, Wang Xin, Qu Liangwei, Chen Bailin, Sun Ya-Ping
Department of Chemistry, Clemson University, South Carolina 29634-0973, USA.
J Am Chem Soc. 2005 May 25;127(20):7517-20. doi: 10.1021/ja050342a.
The detection of nanotube carbons in solution by (13)C NMR is reported. The highly soluble sample was from the functionalization of (13)C-enriched single-walled carbon nanotubes (SWNTs) with diamine-terminated oligomeric poly(ethylene glycol) (PEG(1500N)). The ferromagnetic impurities due to the residual metal catalysts were removed from the sample via repeated magnetic separation. The nanotube carbon signals are broad but partially resolved into two overlapping peaks, which are tentatively assigned to nanotube carbons on semiconducting (upfield) and metallic (downfield) SWNTs. The solid-state NMR signals of the same sample are similarly resolved. Mechanistic and practical implications of the results are discussed.
报道了通过(13)C核磁共振检测溶液中的纳米管碳。高溶解性样品来自富含(13)C的单壁碳纳米管(SWNTs)与二胺封端的低聚聚乙二醇(PEG(1500N))的功能化反应。通过反复磁分离从样品中去除了由于残留金属催化剂导致的铁磁杂质。纳米管碳信号很宽,但部分分辨为两个重叠峰,初步将其归属于半导体(高场)和金属(低场)单壁碳纳米管上的纳米管碳。同一样品的固态核磁共振信号也得到了类似的分辨。讨论了该结果的机理和实际意义。