Acepentalene Membrane Sheet: A Metallic Two-Dimensional Carbon Allotrope with High Carrier Mobility for Lithium Ion Battery Anodes

Abstract

The assembly paths of a 2D porous carbon allotrope designed with acepentalene organic molecules are rationally proposed in theory. The polymerized acepentalene membrane sheet with hexagonal conjunction (h-PAMS) shows high stability. Its π-bands hold Dirac fermion-like characteristics, with the Dirac point located below the Fermi level at the Γ point, crossing the Fermi surface to enable high mobility charge carriers. In addition, it has anisotropic in-plane mechanical properties and can withstand strain loading as large as 0.9 eV/atom energy cost against structural collapse. The synergistic effects of Li adsorption and Li surface clustering result in 676 mAh/g capacity with a low average open-circuit voltage, making h-PAMS a promising lithium ion battery anode material. Furthermore, the barriers for Li diffusion on the h-PAMS and penetration through the porous hole are only 0.35 and 0.61 eV, respectively. The space expansion during the charge–discharge process is only about 10% of the stacked multilayer. Our studies show the possibility of bottom-up fabrication of the h-PAMS and its fascinating properties for high-performance nanoelectronics and Li ion battery anodes, calling for further investigations in both theory and experiment.