Ericson Lars M, Pehrsson Pehr E
Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375, USA.
J Phys Chem B. 2005 Nov 3;109(43):20276-80. doi: 10.1021/jp052364p.
The effect of aggregation on surfactant-suspended individual single-walled carbon nanotube (SWNT) Raman spectroscopy has been explored in the context of dielectrophoretic separation. The Raman spectra of individual surfactant-suspended HiPco SWNTs deposited on a substrate and the same suspension deposited via dielectrophoresis were compared as a function of iterative aggregation states. The evolution of the samples' radial breathing modes and tangential modes at multiple excitation wavelengths (514, 633, and 785 nm) illustrates a direct correlation between changes in the Raman spectra and a broadening and downshifting of resonance transition energies. Dielectrophoresis samples exhibited Raman changes similar to control samples, indicating characterization of electronic separation is compromised by aggregation effects.
在介电泳分离的背景下，研究了聚集对表面活性剂悬浮的单个单壁碳纳米管（SWNT）拉曼光谱的影响。将沉积在基底上的单个表面活性剂悬浮的HiPco SWNT的拉曼光谱与通过介电泳沉积的相同悬浮液的拉曼光谱作为迭代聚集状态的函数进行了比较。在多个激发波长（514、633和785 nm）下，样品的径向呼吸模式和切向模式的演变说明了拉曼光谱变化与共振跃迁能量的展宽和下移之间的直接相关性。介电泳样品表现出与对照样品相似的拉曼变化，表明电子分离的表征受到聚集效应的影响。
