Electronic, Mechanical and LIB Anode Performance of TPDH-Nanotubes—From Ab Initio to Classical Molecular Dynamics Simulations

Tetra-Penta-Deca-Hexa-graphene (TPDH-gr) is a new 2D carbon allotrope with attractive electronic and mechanical properties [1]. It is composed of tetragonal, pentagonal, and hexagonal carbon rings. When TPDH-graphene is sliced into quasi-one-dimensional (1D) structures like nanoribbons, it exhibits a range of behaviors, from semi-metallic to semiconducting and unconventional ionic diffusion pathways for lithium ion batteries (LIB) anode application [2]. An alternative approach to achieving these desirable electronic properties is the creation of nanotubes (TPDH-NTs), which present a more reactive sites compared to TPDH-gr. In the present work, we carried out a comprehensive study of electronic, mechanical and LIB anode performance of TPDH-NTs combining Density Functional Theory (DFT) and Classical Reactive Molecular Dynamics (MD). Our results show structural stability and a chiral dependence on mechanical properties. Similarly to standard carbon nanotubes, TPDH-NT can be metallic or semiconductor. MD results show Young's modulus values exceeding 700 GPa showed a rigid behavior, except for nanotubes with very small radii. However, certain chiral TPDH-NTs (n,m) display values both below and above 700 GPa, particularly for those with small radii. The analyses of the angle and C-C bond length distributions underscore the significance of the tetragonal and pentagonal rings in determining the mechanical response of TPDH-NTs (n,0) and (0,n), respectively. On the other hand, we corroborated a TPDH-gr as a promising anode material for LIB applications, with a high theoretical capacity of C = 1116 mA h/g and low diffusion barriers (&lt; 0.20 eV), closed to graphene values [3]. These results indicate that applicability of TPDH-NTs as an anode of LIB can be improving the diffusion lithium ion, due to curvature effects and chirality. Therefore, all these results show that TPDH-NTs could be possible candidates to be applied as an anode in lithium ion batteries.<br/>References:<br/>[1] Bhattacharya, D., & Jana, D. (2021). TPDH-graphene: A new two dimensional metallic carbon with NDR behaviour of its one dimensional derivatives. Physica E: Low-dimensional Systems and Nanostructures,127, 114569.<br/>[2] Fullerens, Graphenes and Nanotubes. (2018). Elsevier.<br/>[3] Rajkamal,A., & Thapa,R. (2019). Carbon Allotropes as Anode Material for Lithium Ion Batteries. Advanced Materials Technologies,4(10), 1900307.