Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Studying the local character of Raman features of single-walled carbon nanotubes along a bundle using TERS | Peica et al. Nanoscale Research Letters 2011 6 174 http content 6 1 174 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Studying the local character of Raman features of single-walled carbon nanotubes along a bundle using TERS Niculina Peica Christian Thomsen Janina Maultzsch Abstract Here we show that the Raman intensity of the G-mode in tip-enhanced Raman spectroscopy TERS is strongly dependent on the height of the bundle. Moreover using TERS we are able to position different single-walled carbon nanotubes along a bundle by correlating the observed radial breathing mode RBM with the AFM topography at the measuring point. The frequency of the G- mode behaves differently in TERS as compared to far-field Raman. Using the RBM frequency the diameters of the tubes were calculated and a very good agreement with the G--mode frequency was observed. Introduction Tip-enhanced Raman spectroscopy TERS became a very useful technique in studying the optical properties of carbon nanotubes 1-6 . A previous study 7 on the detection of single-walled carbon nanotubes SWCNT by using TERS concentrated on showing the G-mode and the radial breathing mode RBM from a nanometer-sized region that could not be visible in the micro-Raman measurements. Another report 8 has focused on studying the variations in the Raman spectra of the G-mode and RBM by changing the polarization conditions and has shown different behaviors for the two distinct modes. Identification of the chiral indices of SWCNT through the observed radial breathing mode RBM in near-field Raman and photoluminescence PL of the nanotubes was reported as well 9 . Combining near-field PL and near-field Raman imaging Hartschuh et al. 10 observed higher near-field enhancements using PL and suggested that using these two techniques for the study of individual SWCNTs it should be possible to correlate the structural defects with the emission properties of the nanotubes. Recently Roy
