Research Article First-Principle Studies of the Structural, Electronic, and Optical Properties of Double-Walled Carbon Boron Nitride Nanostructures Heterosystem under Various Interwall Distances YahayaSaaduItas, 1 AbdussalamBalarabeSuleiman, 2 ChifuE.Ndikilar, 2 AbdullahiLawal, 3 Razif Razali, 4 Ismail Ibrahim Idowu, 2 Mayeen Uddin Khandaker , 5,6 Amina Muhammad Danmadami, 1 Pervaiz Ahmad , 7 Talha Bin Emran, 8 and Mohammad Rashed Iqbal Faruque 9 1 Department of Physics, Bauchi State University Gadau, PMB 65, Gadau, Bauchi, Nigeria 2 Department of Physics, Federal University, Dutse, Nigeria 3 Department of Physics, Federal ollege of Education, Zaria, Nigeria 4 Department of Physics Faculty of Science, Universiti Teknologi, Johor Bahru, Malaysia 5 Department of General Educational Development, Faculty of Science and Information Technology, Dafodil International University, DIU Rd, Dhaka 1341, Bangladesh 6 entre for Applied Physics and Radiation Technologies, School of Engineering and Technology, Sunway University, Bandar Sunway 47500, Selangor, Malaysia 7 Department of Physics, University of Azad Jammu and Kashmir, Muzafarabad 13100, Pakistan 8 Department of Pharmacy, BG Trust University Bangladesh, hittagong 4381, Bangladesh 9 Space Science entre, Institute of limate hange, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor DE, Malaysia Correspondence should be addressed to Mayeen Uddin Khandaker; mayeenk@diu.edu.bd Received 4 November 2022; Revised 17 December 2022; Accepted 18 March 2023; Published 7 April 2023 Academic Editor: Ashanul Haque Copyright © 2023 Yahaya Saadu Itas et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Structural, electronic, and optical properties of a new combined system of carbon and boron nitride nanotubes are studied using the DFT frst principles as implemented in Quantum ESPRESSO codes. Te corrections to the quasi•particle energies were studied via GW hybrid functional implemented in the YAMBO code within the many•body perturbation theory. Te studies were performed under diferent interwall distances of 3.0nm, 2.5 nm, and 1.5nm between CNTs and BNNTs. Te results showed that the structural properties demonstrated high stability of the double•walled carbon boron nitride nanotube (DWCBNNT) systems under interwall distance (IWD) of 3.00 nm, 2.50 nm, and 1.50 nm. Results also demonstrated an inverse variation between the IWD and the diameter of the DWCBNNT system. In terms of the electronic properties, all three confgurations of the DWCBNNTs reveal semiconducting behavior under KS•DFT showing a direct band gap of 3.30e, 1.79e, and 0.81 e under IWDof3.0nm,2.5nm,and1.5nm,respectively.Furthermore,thebandgapoftheDWCBNNTincreaseswithanincreaseinIWD (decrease in inner tube diameter) and decreases with a decrease in IWD (increase in inner tube diameter). In all three cases, the bands are formed by the molecular orbitals of the armchair CBNNTwhich are transformed to a series of continuous energy levels; the behaviors of electrons that formed the heterostructure are related to the behavior of electrons in B, C, and N atoms. From the optical properties perspective, the studies were conducted in parallel and perpendicular directions to the nanotubes’ axes. Te presence of static dielectric functions in parallel direction at 3.3, 3.4, and 4.5 for nanotubes under 3.0 nm, 2.5 nm, and 1.5 nm demonstrated optical refraction. Refractions were also observed in directions perpendicular to the nanotubes. Furthermore, optical refections occur when there is a higher absorption. Te ability of these CBNNT hybrid systems to refract in all directions revealed the most exciting properties of the armchair CBNNT suitable to be used in magnifying glass materials. Te fndings further imply that the optical absorption coefcient is inversely related to the diameter of the nanotubes and is directly correlated to the band gap. Hindawi Journal of Chemistry Volume 2023, Article ID 4574604, 12 pages https://doi.org/10.1155/2023/4574604