Signatures of Chemical Dopants in Simulated Resonance Raman Spectroscopy of Carbon Nanotubes

Abstract

Single-walled carbon nanotubes (SWCNTs) with organic sp2- or sp3-hybdridization defects allow for robust tunability in many optoelectronic properties in these topologically interesting quasi-one-dimensional materials. Recent resonant Raman experiments have discovered new features in the intermediate frequency region upon functionalization and change with the degree of functionalization as well as with interactions between defect sites. In this letter, we report ab initio simulated near-resonant Raman spectroscopy results for pristine and chemically functionalized SWCNT models and find new features concomitant to experimental observations. We are able to assign the character of these features by varying the frequency of the external Raman laser frequency near the defect-induced E11* optical transition using a perturbative treatment to the electronic structure of the system. Obtained insights establish relationships between nanotube atomistic structure and Raman spectra facilitating further exploration of SWCNTs with tunable optical properties tuned by chemical doping.

Optically active defects in carbon nanotubes via chlorination: computational insights

“…However, the efficient emission of chlorinated SWCNTs is possible only for neutral systems when chlorine adducts are placed close to each other RSC Applied Interfaces Paper at very small concentrations. These findings provide valuable insights into the photophysical and structural properties of chlorinated chiral SWCNTs, which will be instrumental in guiding new synthesis procedures [21][22][23][24][25][26][27][28][29] and characterization techniques 22,36,46,78,79 allowing for chemical control over emission efficiency in SWCNTs.…”

“…Linear optical 24,33,34,36,37,46,85,[89][90][91] and vibronic 22,36,79,[92][93][94][95][96][97] spectroscopy are some of the simplest ways to probe sp 3 -defect states in SWCNTs. Other methods also exist, such as electroluminescence, 98 transmission electron microscopy (TEM), 99 and atomic force microscopy (AFM).…”