Investigation on the Structure and Electronic States of N/CNT (8,0) -Graphene with 1:1 and 1:2 Nitrogen-to-Carbon Layering Ratios

The self-consistent charge density functional tight binding (SCC-DFTB) algorithm was employed to investigate bamboo-like zigzag N/CNT (8,0) -graphene, which were characterized through an analysis of packing geometries, bond lengths, internal energy, energy gaps, chemical potentials, Mulliken populations, charge density differences, and molecular orbitals at the HOMO and LUMO energy levels. Reducing the nitrogen-to-carbon ratio increased the number of seamless N/CNT (8,0) -graphene configurations with defective porous graphene, which the number of seamless bonding configurations for N/CNT (8,0) -graphene increases from five configurations at a nitrogen-to-carbon atom ratio of 1:1 to nine configurations at a nitrogen-tocarbon atom ratio of 1:2. Enhancing the proportion of nitrogen atoms substituting for carbon atoms in the layers elevated the intrinsic energy and chemical potential of N/CNT (8,0) -graphene. The energy gap range of N/CNT (8,0) -graphene configurations with nitrogen-to-carbon (N:C) atomic ratio of 1:1 was 0.1 eV wider than that with a ratio of 1:2. As the N substitution ratio decreased, the difference Max-Min Mulliken population on N atoms diminished significantly from 0.78±0.03 to 0.11±0.05, whereas that on C atoms increased. At the junction of these seamlessly configurations, the amount of charge gained and lost by the carbon atoms that form eight carbon-carbon bonds were very obvious both [-0.19,0.13] and [-0.12,0.06], and the transfer of charge from the carbon atoms on the N/CNT (8,0) to the graphene carbon atoms occurs.The three-dimensional system featuring a bamboo-like nitrogen/carbon nanotubegraphene composite structure also provides a three-dimensional interconnected network for electron transport and ion diffusion. The information provides a new approach for developing lightweight materials that can absorb electromagnetic waves after encapsulating transition metal atoms.