Systematic investigation of capacitances in functionalized MXene supercapacitors $M_{n+1}C_nO_2$, $M=Ti,V,Nb,Mo$

TL;DR

This study uses first-principles calculations to systematically analyze the capacitance mechanisms in pristine and functionalized MXene materials, providing atomic-level insights into their electrochemical performance.

Contribution

It offers a comprehensive atomic-scale understanding of capacitance sources in various MXenes, advancing knowledge beyond limited experimental data.

Findings

Detailed analysis of capacitance sources in MXenes

Insights into the effects of functionalization on capacitance

Correlation of computational results with experimental data

Abstract

MXene, the class of two-dimensional materials, has been found to be useful as potential electrode materials for electrochemical capacitors. Although experimental investigation on the electrochemical performances of a few MXenes have been carried out with exciting results, a complete understanding of their atomic scale behaviour is yet to be done. Using first-principles electronic structure methods, we perform a systematic investigation of the capacitances in pristine and functionalised MXenes $M_{n+1}C_{n}O_{2}$ where $M=Ti,V,Nb$ and $Mo$. We provide results on each of the three sources of the capacitance and analyse them in detail for a complete understanding of their behaviour. The interpretation of the experimental results, wherever available, in the light of our computations,provides useful insights.