Ti3C2Tx MXene Electrode-Electrolyte Interface Reactions at Different Stages of Charge/Discharge in Lithium and Sodium Half-Cells

Abstract

Energy storage technologies necessitates efficient, cost effective, and durable storage systems like Li-ion batteries (LIBs), with high energy density. Emerging 2D materials like MXenes have become significant for battery applications. Herein, titanium carbide (Ti₃C₂T_x) synthesized and lattice engineered via -OH surface terminations removal by thermal processing is well explained. The synthesized samples were subjected to annealing at 250 and 500 °C. All the samples were characterized using XRD, TEM, XPS, etc. Subsequently, they were tested in the half-cell configuration for both lithium and sodium ion batteries (NIBs). It is observed that the best performance for lithium-ion storage capacity was 200 mAh/g at 50 mA/g and 125 mAh/g at the same specific current for sodium-ion storage for the 500 °C processed sample. However, for both the systems the cycling stability was exceptional maintaining high retention till the end of 1000 cycles. To establish the performance, electrochemical impedance and ex situ XPS results at different voltage of 1^st charge/discharge were correlated for the best sample. Thus, providing information that is unavailable in the literature on MXene-electrolyte interactions, kinetics and the chemical nature of solid-electrolyte interface layer for both lithium and sodium-ion batteries.