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The development of an asymmetrical field-flow fractionation (AsFIFFF) method for separating gold nanorods (GNR) is reported. Collected fractions containing GNR subpopulations with aspect ratios, sizes, and shapes which are more narrowly dispersed than the original population were further characterized by UV-vis apectroscopy and transmission electron microscopy. This ability to obtain different sizes and shapes of nanoparticles enabled the evaluation of a new approach to estimating the retention time and hydrodynamic size of nanorods and the investigation of GNR optical properties at a previously unattainable level of detail. Experimental results demonstrate that the longitudinal surface plasmon absorption maximum of GNRS is correlated with the effective particle radius in addition to the aspect ratio. This may account for some of the variabilities reported in published empirical data from different research groups and supports reports of simulated absorption spectra of GNRs of different physical dimensions. The use of AsFIEFF with dual UV-vis detection to rapidly assess relative changes in GNP. subpopulations was demonstrated for irregularly shaped gold nanoparticles formed at different synthesis temperatures. [ABSTRACT FROM AUTHOR]

In conjunction with environmentally benign ionic liquid electrolytes, vertically-aligned carbon nanotubes (VA-CNTs) sheathed with and without a coaxial layer of vanadium oxide (V(2)O(5)) were used as both cathode and anode, respectively, to develop high-performance and high-safety lithium-ion batteries. The VA-CNT anode and V(2)O(5)-VA-CNT cathode showed a high capacity (600 mAh g(-1) and 368 mAh g(-1), respectively) with a high rate capability. This led to potential to achieve a high energy density (297 Wh kg(-1)) and power density (12 kW kg(-1)) for the prototype batteries to significantly outperform the current state-of-the-art Li-ion batteries.