$\beta$-Irida-Graphene: A New 2D Carbon Allotrope for Sodium-Ion Battery Anodes

TL;DR

This paper introduces a novel 2D carbon material, $eta$-Irida-graphene, showing promising properties as an anode for sodium-ion batteries with high capacity and stability based on computational simulations.

Contribution

The study presents the design and computational validation of $eta$-Irida-graphene as a new stable, conductive 2D carbon allotrope suitable for sodium-ion battery anodes.

Findings

Demonstrates high thermal, dynamical, and mechanical stability of $eta$-IG.

Shows efficient sodium-ion mobility with low energy barriers.

Predicts a high specific capacity of 554.5 mAh/g.

Abstract

The quest for sustainable and efficient energy storage has driven the exploration of sodium-ion batteries (SIBs) as promising alternatives to lithium-ion systems. However, the larger ionic radius of sodium poses intrinsic challenges such as slow diffusion and structural strain in conventional electrode materials. As a contribution to addressing these limitations, the \b{eta}-Irida-graphene ($\beta$-IG) is herein introduced, a novel two-dimensional (2D) carbon allotrope derived from Irida-graphene, featuring a diverse polygonal lattice of 3-, 4-, 6-, 8-, and 9-membered carbon rings. Through density functional theory and ab initio molecular dynamics simulations, $\beta$-IG demonstrated remarkable thermal, dynamical, and mechanical stability, coupled with intrinsic conductive character and efficient sodium-ion mobility (energy barriers < 0.30 eV). Furthermore, the adsorption of sodium ions was energetically favorable, delivering an impressive predicted specific capacity of 554.5 mAh/g. The reported findings highlight $\beta$-IG as a good potential anode candidate for next-generation SIBs, offering high-rate performance and structural robustness, and expanding the functional design space for advanced carbon-based electrode materials.