Raman Spectroscopy Study of Isolated Double-Walled Carbon Nanotubes with Different Metallic and Semiconducting Configurations

Abstract

A double-walled carbon nanotube (DWNT) provides the simplest system to study the interaction between concentric layers in carbon nanotubes. The inner and outer walls of a DWNT can be metallic (M) or semiconducting (S), and each of the four possible configurations (M@M, M@S, S@S, S@M) has different electronic properties. Here we report, for the first time, detailed Raman spectroscopy experiments carried out on individual DWNTs, where both concentric tubes are measured under resonance conditions, in order to understand the dependence of their electronic and optical properties according to their configuration. Interestingly, for the three DWNTs that were studied, the inner-outer tube distance (e.g., 0.31-0.33 nm) was less than the interlayer spacing in graphite. We believe these results have important implications in the fabrication of electronic devices using different types of S and M tubular interconnects.

Wall-to-wall stress induced in (6,5) semiconducting nanotubes by encapsulation in metallic outer tubes of different diameters: A resonance Raman study of individual C60-derived double-wall carbon nanotubes

“…Performing AFM and acquiring Raman spectra with many E laser on isolated DWNTs is feasible [12] but also experimentally challenging. While attempting to increase the throughput of the above mentioned technique, we discovered that it is also possible to use less AFM time and only one laser line and still be almost certain that we are in resonance with the inner and outer tubes of the same DWNT.…”

“…In order to quantitatively determine which specific inner and outer tubes actually form each DWNT, one must perform experiments on individual DWNTs [12]. Therefore, in the present work individual C 60 -DWNTs have been dispersed on a substrate and studied independently.…”

Strong and stable photoluminescence from the semiconducting inner tubes within double walled carbon nanotubes

“…We have used slit widths of 10 nm and scan steps of 0.5 nm for obtaining excitation and emission spectra, respectively. Each peak in the PL map corresponds to an excitation involving the second excitonic transition E 22 S of the semiconducting inner tubes of the DWNTs and of semiconducting SWNTs and the emission from the corresponding first excitonic transition E From these PL maps, we observed a redshift of both the E 11 and E 22 from the semiconducting inner tubes of the DWNTs as compared to SWNTs. This energy difference ͑⌬E ii = E ii DWNT − E ii SWNT ͒ for each individual system is summarized in Table I.…”

Экспериментальное Исследование Динамики Решетки Индивидуальных Полупроводниковых Двустенных Углеродных Нанотрубок: Тангенциальные G-Моды

“…Хотя ранее и было проведено изучение индиви-дуальных полупроводниковых ДУНТ расположенных на подложке [11][12][13], в этих работах структуру двустенных нанотрубок идентифицировали косвенным способом с 328…”

“…Хотя ранее и было проведено изучение индиви-дуальных полупроводниковых ДУНТ расположенных на подложке [11][12][13] (27,17). Спектры нормализованы по интенсивности G-моды для иллюстративных целей.…”