Match!

Determination of the Surfactant Density on SWCNTs by Analytical Ultracentrifugation

Published on Nov 22, 2010in Chemistry: A European Journal5.16
· DOI :10.1002/chem.200903461
Claudia Backes32
Estimated H-index: 32
(FAU: University of Erlangen-Nuremberg),
Engin Karabudak9
Estimated H-index: 9
(UT: University of Twente)
+ 3 AuthorsWendel Wohlleben40
Estimated H-index: 40
Abstract
We report on the extensive characterization of single-walled carbon nanotubes (SWCNTs) dispersed in a variety of surfactants, such as sodium dodecyl benzene sulfonate (SDBS), sodium cholate (SC), and three synthesized perylene-based surfactants, by using differential sedimentation in H2O and D2O. Multidimensional evaluation of the absorption profiles over radius, wavelength, and time allows the determination of the anhydrous specific volumes of the SWCNT–surfactant complexes as well as the concentration of the surfactant reservoir in free micelles with very slow sedimentation coefficients (<1 Svedberg). Among the perylene bisimide surfactants, the smallest derivative is densely adsorbed on the nanotube backbone with an anhydrous specific volume significantly above that of SC or SDBS. Bulky Newkome dendritic groups on one or both ends of the perylene moiety gradually reduce the adsorption density, in accord with the absolute adsorption between 0.66 and 1.7 mmol surfactant per gram SWCNTs. Furthermore, hydrodynamic analysis reveals that SDBS favors the “tails-on” configuration. The distribution of sedimentation coefficients of SWCNTs prepared by high-pressure carbon monoxide decomposition (HiPco) is broader and shifted to faster sedimentation than those prepared by using cobalt–molybdenum catalysis (CoMoCAT), which reflects the polydispersity in diameter and length.
  • References (39)
  • Citations (25)
📖 Papers frequently viewed together
200813.90ACS Nano
88 Citations
1,611 Citations
18 Citations
78% of Scinapse members use related papers. After signing in, all features are FREE.
References39
Newest
#1Claudia Backes (FAU: University of Erlangen-Nuremberg)H-Index: 32
#2Cordula D. Schmidt (FAU: University of Erlangen-Nuremberg)H-Index: 13
Last. Andreas Hirsch (FAU: University of Erlangen-Nuremberg)H-Index: 76
view all 6 authors...
The synthesis of perylene-based single-walled carbon nanotube (SWCNT) surfactants and the dispersion and exfoliation of SWCNTs in water by a variety of designed surfactants is investigated. The quality of the nanotube dispersions is evaluated by optical absorption and emission spectroscopy, zeta-potential measurements and statistical atomic force microscopy (AFM). Significantly the dispersion efficiency can be increased at higher pH, as water solubility of the surfactants is ensured by periphera...
110 CitationsSource
#1Engin Karabudak (MPG: Max Planck Society)H-Index: 9
#2Wendel WohllebenH-Index: 40
Last. Helmut Cölfen (MPG: Max Planck Society)H-Index: 74
view all 3 authors...
A multiwavelength UV/vis detector for the analytical ultracentrifuge (MWL-AUC) has been developed recently. In this work, β-carotene–gelatin composite particles are investigated with MWL-AUC. Band centrifugation with a Vinograd cell is used to ensure maximum sample separation. Spectral changes of the system are observed in dependence of the sedimentation coefficient and are attributed to a previously unknown inhomogeneity of the β-carotene chemical composition with both H- and J-aggregates coexi...
20 CitationsSource
#1Helmut Cölfen (MPG: Max Planck Society)H-Index: 74
#2Thomas M. Laue (UNH: University of New Hampshire)H-Index: 35
Last. Borries Demeler (University of Texas System)H-Index: 43
view all 11 authors...
Progress in analytical ultracentrifugation (AUC) has been hindered by obstructions to hardware innovation and by software incompatibility. In this paper, we announce and outline the Open AUC Project. The goals of the Open AUC Project are to stimulate AUC innovation by improving instrumentation, detectors, acquisition and analysis software, and collaborative tools. These improvements are needed for the next generation of AUC-based research. The Open AUC Project combines on-going work from several...
35 CitationsSource
The effect of substrate curvature on surfactant self-assembly has been studied using all-atom molecular-dynamics simulations. We studied aqueous sodium-dodecyl-sulfate (SDS) surfactants on graphite, on the outer surface of single walled carbon nanotubes (SWNTs) and within SWNTs. Our results reveal that although the chemical nature of the substrates is constant, the self-assembled structures change significantly as the curvature varies. For example, at large surface density, SDS surfactants yield...
43 CitationsSource
#1Christian Ehli (FAU: University of Erlangen-Nuremberg)H-Index: 20
#2Christian Oelsner (FAU: University of Erlangen-Nuremberg)H-Index: 8
Last. Andreas Hirsch (FAU: University of Erlangen-Nuremberg)H-Index: 76
view all 9 authors...
Using carbon nanotubes in electronic or photovoltaic devices generates active metastable states. These elusive species are hard to characterize because of the polydisperse and aggregate nature of nanotube bundles. A complete characterization of the radical–ion pair state has now been achieved using a range of techniques.
174 CitationsSource
#1Claudia Backes (FAU: University of Erlangen-Nuremberg)H-Index: 32
#2Frank Hauke (FAU: University of Erlangen-Nuremberg)H-Index: 34
Last. Andreas Hirsch (FAU: University of Erlangen-Nuremberg)H-Index: 76
view all 4 authors...
HiPco and CoMoCAT single-walled carbon nanotubes (SWCNT) were fractionated with the aid of a novel perylene bisimide surfactant by combined co-surfactant and replacement density gradient ultracentrifugation (DGU).
31 CitationsSource
#1Claudia BackesH-Index: 32
#2Cordula D. SchmidtH-Index: 13
Last. Andreas Hirsch (FAU: University of Erlangen-Nuremberg)H-Index: 76
view all 5 authors...
The aqueous dispersion of SWCNTs in the presence of the water-soluble perylene derivatives 1−3 is reported. Significantly, even very low concentrations of the perylenes such as 0.01 wt% of the amphiphilic derivative 3, cause an efficient dissolution of the SWCNTs in water accompanied by a very pronounced individualization. The individualization of SWCNTs in water after ultrasonication in the presence of water-soluble aromatic perylenes was investigated in detail by absorption, emission, and Rama...
113 CitationsSource
#1Alexander A. Green (NU: Northwestern University)H-Index: 34
#2Matthew C. Duch (NU: Northwestern University)H-Index: 10
Last. Mark C. Hersam (NU: Northwestern University)H-Index: 82
view all 3 authors...
Current methods of synthesizing single-walled carbon nanotubes (SWNTs) result in racemic mixtures that have impeded the study of left- and right-handed SWNTs. Here we present a method of isolating different SWNT enantiomers using density gradient ultracentrifugation. Enantiomer separation is enabled by the chiral surfactant sodium cholate, which discriminates between left- and right-handed SWNTs and thus induces subtle differences in their buoyant densities. This sorting strategy can be employed...
106 CitationsSource
#1Borries Demeler (University of Texas Health Science Center at San Antonio)H-Index: 43
#2Emre H Brookes (University of Texas Health Science Center at San Antonio)H-Index: 17
Last. Luitgard Nagel-Steger (HHU: University of Düsseldorf)H-Index: 20
view all 3 authors...
Abstract A computational approach for fitting sedimentation velocity experiments from an analytical ultracentrifuge in a model-independent fashion is presented. This chapter offers a recipe for obtaining high-resolution information for both the shape and the molecular weight distributions of complex mixtures that are heterogeneous in shape and molecular weight and provides suggestions for experimental design to optimize information content. A combination of three methods is used to find the solu...
22 CitationsSource
#1Kazuhiro YanagiH-Index: 27
#2Toshie IitsukaH-Index: 1
Last. Hiromichi KatauraH-Index: 63
view all 4 authors...
The separation of metallic and semiconducting single-wall carbon nanotubes (SWCNTs) was achieved using sucrose as a gradient medium in density-gradient ultracentrifugations (sucrose-DGU). By lowering the temperature during sucrose-DGU and tuning the concentrations of the surfactants, metallic and semiconducting SWCNT samples were obtained in high purity. The purity of the metallic and the semiconducting SWCNTs obtained by the sucrose-DGU was estimated to be 69% and 95%, respectively, from their ...
40 CitationsSource
Cited By25
Newest
Source
#1Xun Gong (MIT: Massachusetts Institute of Technology)H-Index: 8
#2Minkyung Park (MIT: Massachusetts Institute of Technology)H-Index: 2
Last. Michael S. Strano (MIT: Massachusetts Institute of Technology)H-Index: 82
view all 7 authors...
: Colloidal dispersions of nanomaterials are often polydisperse in size, significantly complicating their characterization. This is particularly true for materials early in their historical development due to synthetic control, dispersion efficiency, and instability during storage. Because a wide range of system properties and technological applications depend on particle dimensions, it remains an important problem in nanotechnology to identify a method for the routine characterization of polydi...
1 CitationsSource
#1Katharina Huth (FU: Free University of Berlin)H-Index: 4
#2Mareen Glaeske (FU: Free University of Berlin)H-Index: 4
Last. Rainer Haag (FU: Free University of Berlin)H-Index: 66
view all 11 authors...
: Fluorescent nanomaterials are expected to revolutionize medical diagnostic, imaging, and therapeutic tools due to their superior optical and structural properties. Their inefficient water solubility, cell permeability, biodistribution, and high toxicity, however, limit the full potential of their application. To overcome these obstacles, a water-soluble, fluorescent, cytocompatible polymer-single-walled carbon nanotube (SWNT) complex is introduced for bioimaging applications. The supramolecula...
4 CitationsSource
#1Engin Karabudak (İzmir Institute of Technology)H-Index: 9
#2Emre H Brookes (University of Texas Health Science Center at San Antonio)H-Index: 17
Last. Helmut Cölfen (MPG: Max Planck Society)H-Index: 74
view all 11 authors...
1 CitationsSource
#1Engin Karabudak (İzmir Institute of Technology)H-Index: 9
#2Emre H Brookes (University of Texas Health Science Center at San Antonio)H-Index: 17
Last. Helmut Cölfen (MPG: Max Planck Society)H-Index: 74
view all 11 authors...
We report an unsurpassed solution characterization technique based on analytical ultracentrifugation, which demonstrates exceptional potential for resolving particle sizes in solution with sub-nm resolution. We achieve this improvement in resolution by simultaneously measuring UV/Vis spectra while hydrodynamically separating individual components in the mixture. By equipping an analytical ultracentrifuge with a novel multi-wavelength detector, we are adding a new spectral discovery dimension to ...
12 CitationsSource
#1Elijah J. Petersen (NIST: National Institute of Standards and Technology)H-Index: 36
#2D. Xanat Flores-Cervantes (Eawag: Swiss Federal Institute of Aquatic Science and Technology)H-Index: 5
Last. Michael R. Winchester (NIST: National Institute of Standards and Technology)H-Index: 16
view all 14 authors...
Carbon nanotubes (CNTs) have numerous exciting potential applications and some that have reached commercialization. As such, quantitative measurements of CNTs in key environmental matrices (water, soil, sediment, and biological tissues) are needed to address concerns about their potential environmental and human health risks and to inform application development. However, standard methods for CNT quantification are not yet available. We systematically and critically review each component of the ...
45 CitationsSource
#1Stephanie LamH-Index: 9
#2Ming ZhengH-Index: 41
Last. Jeffrey A. FaganH-Index: 29
view all 3 authors...
Accurate characterization of dispersed-phase nanoparticle properties such as density, size, solvation, and charge is necessary for their utilization in applications such as medicine, energy, and materials. Herein, analytical ultracentrifugation (AUC) is used to quantify bile salt surfactant adsorption on length sorted (7,6) single-wall carbon nanotubes (SWCNTs) as a function of bulk surfactant concentration and in the presence of varying quantities of a monovalent salt—sodium chloride. These mea...
7 CitationsSource
#1Johannes Walter (FAU: University of Erlangen-Nuremberg)H-Index: 16
#2Doris Segets (FAU: University of Erlangen-Nuremberg)H-Index: 19
Last. Wolfgang Peukert (FAU: University of Erlangen-Nuremberg)H-Index: 47
view all 3 authors...
5 CitationsSource
#1Engin Karabudak (İzmir Institute of Technology)H-Index: 2
#2Helmut Cölfen (University of Konstanz)H-Index: 74
The multiwavelength (MWL) detector is a new type of absorption detector for AUC. The commercial absorption detector of the Beckman Coulter XL-A AUC can only handle a single wavelength per scan with the possibility to scan at maximum 3 wavelengths, whereas MWL-AUC can handle all the wavelengths in the UV/Vis region at one time. The result is impressive since now a full spectral dimension is added to each single scan. In this chapter, we are explaining development history, instrumentation, and fut...
2 CitationsSource
#1Franziska Toni (FAU: University of Erlangen-Nuremberg)H-Index: 5
#2Haichen Xing (FAU: University of Erlangen-Nuremberg)H-Index: 2
Last. Wolfgang Peukert (FAU: University of Erlangen-Nuremberg)H-Index: 47
view all 9 authors...
Abstract In this paper, we present a unique process chain for the production of single-walled carbon nanotubes (SWCNT) and document the relationship between the process parameters in gas phase production, the dispersibility of SWCNTs in aqueous solutions of sodium cholate and their properties. SWCNTs were prepared by a “floating catalyst” method using a solution of ferrocene in ethanol as precursor. Production rates in the range from 5 to 20 mg/h were achieved by using an optimized riser reactor...
6 CitationsSource