Semiconducting nanotube

L., Prolonging charge separation in P3ht-SWNT composites using highly enriched semiconducting nanotubes. Nano Lett. 2010,10, 4627-4633. 

Separation of SWNTs based on chirality and diameter with surfactants has also been evidenced by density-gradient ultracentrifugation [86]. Finally, a recent study has demonstrated the separation of semiconducting nanotubes from metallic ones by chemical interaction of the former with attached amine-terminated silane molecules assembled on a silicon wafer. In a separate experiment, metallic nanotubes were also... 

Small shifts of the same bands are observed for nanotubes solutions with Tween but these shifts are smaller (by about 5-7 meV). The greatest shift of bands (up to 70 meV) can be seen for absorption spectra of nanotubes with SDS. So, the interaction between SWNT and surfactant in aqueous solution leads to the increase of the semiconducting nanotubes band gap, especially for a surfactant with a charge group. 

In NIR absorption spectra of aqueous solutions of SWNTs with various surfactants, the bands in the region of the first electronic transition (Eus) in the semiconducting nanotube are shifted to the high energy, as compared with a spectrum of SWNT in KBr. In Raman spectra of aqueous solution of SWNT with different surfactants the intensity of the low-frequency component of the G mode decreases in comparison with spectra of the nanotube in films. In the spectrum of SWNT with SDS the intensity of this component is very weak. 

Apart from mechanical properties, electronic properties of nanotubes are equally important and useful. As observed earlier, both metallic and semiconducting nanotubes are generated depending... 

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