How Do The Localized Strain Fields And Lattice Distortions Induced By Stone-Wales Defects In Single-walled Carbon Nanotubes Affect Their Phonon Confinement And Thermal Transport Properties At The Nanoscale, Particularly In The Presence Of Surface Functionalization?

The presence of Stone-Wales defects in single-walled carbon nanotubes (SWCNTs) introduces localized strain fields and lattice distortions, which significantly impact their phonon confinement and thermal transport properties. These defects, characterized by the formation of pentagon-heptagon pairs, disrupt the otherwise uniform hexagonal lattice, leading to phonon scattering. This scattering confines phonons to smaller regions and reduces their mean free path, thereby decreasing thermal conductivity.

Surface functionalization, the addition of groups or molecules to the nanotube surface, further influences these properties. Functional groups can introduce additional phonon scattering mechanisms, potentially exacerbating the effects of the defects. The interaction between the functional groups and the nanotube lattice may alter phonon modes, either by creating new scattering sites or modifying existing ones.

The combined effect of Stone-Wales defects and surface functionalization typically results in reduced thermal conductivity. Defects scatter phonons, and functionalization may compound this effect, although the extent depends on the type and density of the functional groups. At the nanoscale, where the impact of individual defects is pronounced, these factors significantly influence heat transport, highlighting the importance of considering both structural defects and surface modifications in determining thermal properties.