Density functional investigations on 2D-Be2C as an anode for alkali Metal-ion batteries

TL;DR

This study uses first-principle calculations to explore 2D-Be2C as a promising anode material for alkali metal-ion batteries, highlighting its stability, low diffusion barriers, and high storage capacity.

Contribution

It introduces 2D-Be2C as a novel anode material for Na and K batteries, providing detailed computational analysis of its electrochemical properties.

Findings

Low diffusion barriers for Na and K (0.016 and 0.026 eV)

Maximum open circuit voltage around 1 V for K and 0.5 V for Na

High storage capacity of 1785 Ah/kg

Abstract

Metal-ion batteries are in huge demand to cope with the increasing need for renewable energy, especially in automobiles. In this work, we apply first-principle calculations to examine two-dimensional beryllium carbide (2D-Be2C) as a possible anode material for metal-ion (Na and K) batteries. 2D-Be2C is a semiconductor and becomes metallic by adsorbing metal ions. Negative adsorption energy indicates stable adsorption on the monolayer of Be2C. Alkali metal diffusion barrier and optimum path for minimum energy are studied within the framework of the climbing image nudged elastic band method. Here, six intermediate images are considered between the initial and final states. The lowest diffusion barriers for a single adsorbed Na and K atom are 0.016 and 0.026 eV, respectively. A maximum open circuit voltage of around 1 V is computed for K ions, whereas 0.5 V is for Na ions. Also, the maximum storage capacity of the Be2C monolayer is estimated at 1785 Ah/kg.