2D Homogeneous Holey Carbon Nitride: An Efficient Anode Material for Li-ion Batteries With Ultrahigh Capacity

In present day Li-ion batteries (LIBs) is the most successful and widely used rechargeable batteries. The continuous effort is going on in finding suitable electrode material for LIBs for improved performance in terms of life-time, storage capacity etc. Computational chemistry plays an important role in identifying suitable electrode materials through electronic structure calculation. By employing state of the art density functional theory we herein explored the electronic structure of homogeneous holey carbon nitride monolayers (C_x N₃ , x=10,19) to understand its suitability as electrode material for rechargeable LIB. The monolayers have shown high negative adsorption energy for Li adsorption and more interestingly the band structure of monolayers reveal Dirac semimetallic character thus would exhibit high electronic conductivity. Meanwhile, monolithiation introduces metallicity in these monolayers. The calculated average open circuit voltages of the monolayers lie in the range of 0.45 to 0.09 V, which are typically observed in high performance anode materials. Moreover, these monolayers achieve ultrahigh theoretical specific capacity upto 2092.01 mAh/g and low diffusion barrier from 0.004 to 0.44 eV. Based on our computational study we suggest that, the C_x N₃ monolayers could be a promising anode material in search of low-cost and high performance LIBs.