First-Principles\nCalculations of the Electrical Conductivity\nof Carbon Nanotubes Functionalized with Copper and Nitrogen: Implications\nfor Electronics, Energy Storage, and Nanodevices

In this work, we investigate the electrical conductivity\nof carbon\nnanotubes (CNTs), with a particular focus on the effects of doping.\nUsing first-principles-based approaches, we study the electronic structure,\nphonon dispersion, and electron–phonon scattering to understand\nthe finite-temperature electrical transport properties in CNTs. Our\nstudy covers both prototypical metallic and semiconducting CNTs, with\nspecial emphasis on the influence of typical defects such as vacancies\nand the incorporation of copper or nitrogen, such as pyridinic N,\npyrrolic N, graphitic N, and oxidized N. Our theoretical study shows\nsignificant improvements in the electrical conduction properties of\ncopper-CNT composites, especially when semiconducting CNTs are functionalized\nwith nitrogen. Doping is found to cause significant changes in the\nelectronic density of states near the Fermi level, which affects the\nelectrical conductivity. Calculations show that certain types of functional\ngroups, such as N-pyrrolic, result in more than 30-fold increase in\nthe conductivity of semiconducting CNTs compared to Cu-incorporated\nCNTs alone. For metallic CNTs, the conductivity is in agreement with\nexisting experimental data, and our prediction of significant increases\nin conductivity with N-pyrrolic functional group is consistent with\nrecent experimental results, demonstrating the effectiveness of doping\nin modifying conductivity. Our study provides valuable insight into\nthe electronic properties of doped CNTs and contributes to the development\nof ultrahigh conductivity CNT composites.