Computational Insights into the Influence of Surface Functionalization Groups on Zirconium Carbide MXenes as Anode Materials for Lithium-Ion Batteries

In this study, we employed first-principles calculations to predict the influence of Si, H, O, P, S, Se, F, and Cl surface functionalization on Zr3C2 MXene, serving as an electrode material for lithium-ion batteries (LIBs). The findings show that O, S, Se, F, and Cl surface terminals enhance the stability of bare MXene. The metallic nature of pristine and functionalized MXenes before and after the Li adsorption was revealed by the substantial density of states at the Fermi line. Further, Si, P, S, and Se surface terminals improve the electronic conduction. We identified the optimal positions for Li adsorption and found that Si, O, P, S, and Se functional groups enhance Li adsorption, and the highest adsorption energy is estimated for S functionalization (−2.864 eV). Exceptionally, Zr3C2O2 MXene has suitable open circuit voltage, good cycling stability, and enhanced storage capacity. Our findings affirm that surface functionalization yields favorable outcomes for zirconium carbide MXene and demonstrates oxygen-functionalized MXene with better electrochemical characteristics suitable for LIBs.