Thermal Conductivity Behavior of Zig-Zag Single-Walled(7,0) Carbon Nanotube Using the Nikiforov-Uvarov Method

Abstract

The structural parameters of carbon nanotubes significantly influence thermal transport properties. In this study, the thermal behaviour of a semiconducting zig-zag single-walled (7,0) carbon nanotube was investigated using the Nikiforov–Uvarov (NU) analytical approach. Thermal conductivity was evaluated as a function of temperature, nanotube length, and diameter. The results showed that thermal conductivity increased from [κ₁ W m⁻¹ K⁻¹] at [T₁ K] to a maximum value of [κ₂ W m⁻¹ K⁻¹] at approximately [Tₛ K], after which it gradually decreased due to enhanced phonon scattering effects. Increasing the nanotube length from [L₁ nm] to [L₂ nm] resulted in a corresponding rise in thermal conductivity from [κ₃] to [κ₄ W m⁻¹ K⁻¹], indicating improved phonon transport along longer tubes. Conversely, increasing the nanotube diameter from [D₁ nm] to [D₂ nm] reduced thermal conductivity by approximately [X%], attributed to increased phonon–boundary scattering. The observed thermal transport behavior is governed by the transition between ballistic phonon motion at lower dimensions and scattering-dominated transport at higher temperatures and larger diameters. These findings provide quantitative insight into structure-dependent thermal performance of semiconducting carbon nanotubes for nanoscale thermal management applications