A universal ultracentrifuge spectrometer visualizes CNT-intercalant-surfactant complexes.
A universal ultracentrifuge spectrometer visualizes CNT-intercalant-surfactant complexes.
复制标题
通用超速离心光谱仪可显示 CNT-嵌入剂-表面活性剂复合物。
作者：
E. Karabudak;C. Backes;F. Hauke;Cordula D. Schmidt;H. Cölfen;A. Hirsch;W. Wohlleben
相互作用的溶质形成多个缔合物，通常在系综表征中相互掩蔽。在通常应用的单分子技术中，它们容易受到制备人工制品的影响。为了解决单壁碳纳米管(CNT)分散体在新型表面活性剂-插层剂混合物中的本体表征问题，我们获得了极端重力下的分馏彩色胶片，使得每个胶体组分都被独立地表征。我们结合了超心离心机独特的分馏力！)在沉积过程中的每个时间步t的每个径向位置r处的全吸收光谱Eta)。[8]，用Beckman型XLA型离心机研究了配体附着碳纳米管，该离心机只跟踪单一波长的e(r，t)，需要扩展建模才能进行分析。我们的光谱仪/CCD光谱仪I2.3)添加了第三维，并生成离心机分馏的波长分辨电影e(r，t，}，)。这允许独立的配体和CNT跟踪，而不需要流体动力学建模。我们确定了未纯化的插层剂-表面活性剂-碳纳米管分散体中的相互作用，并通过一种新的无模型评估获得了四个共存的异构体的意外证据。碳纳米管的增溶对于提高这类独特材料的加工性至关重要。尽管通过电泳法、密度梯度超离心法或层析法分离和分选单壁碳纳米管已经取得了进展，但基于碳纳米管的技术还没有实现商业化，因为碳纳米管的分离仅限于个性化的纳米管。14，S)以前已经证明，设计的水溶性过联二亚胺类化合物是优秀的碳纳米管表面活性剂，得到的碳纳米管分散体高达73%，其中高达73%的碳纳米管稳定分散，含有60%的In。
Interacting solutes form mUltiple associates and usually mask each other in ensemble characterization. They are susceptible to preparation artefacts in the single-molecule techniques commonly applied. To overcome the problem of bulk characterization of a single-walled carbon nanotube (CNT) dispersion with a novel surfactant-intercalant mixture, we obtain color movies of fractionation under extreme gravity, such that each colloidal component is characterized independently. We combine the unique fractionation power of ultracentrifugationl!) with full absorption spectra etA) at each radial position r at each time step t during the sedimentation process.[2,3) In ref. [8], ligand attachment CNTs was studied with the Beckman model XLA centrifuge, which tracks only e(r,t) at a single wavelength, requiring extended modeling for analysis. Our spectrometer/CCD opticsI2.3) adds a third dimension and generates wavelength-resolved movies of the centrifuge fractionation e(r,t,},). This allows independent ligand and CNT tracking without hydrodynamic modeling. We identify the interactions in unpurified intercalant-surfactant-CNT dispersions and obtain the unexpected proof of four coexisting heteroassociates by a novel model-free evaluation. Solubilization of carbon nanotubes is of primary importance to increase the processability of this unique class of materials. Despite the progress in separating and sorting SWCNTs by electrophoresis, density gradient ultracentrifugation or chromatography, CNT-based technology has not yet been realized on a commercial scale, as the CNT separation is limited to individualized nanotubes.14,S) It has previously been shown that designed water-soluble perylene bisimide derivatives such as 1 are excellent CNT surfactants, yielding CNT dispersions with up to 73 % of the CNTs stably dispersed and containing 60% of in-