Microwave-etched V₂C MXene-activated carbon hybrid as a high-performance anode material for lithium-ion batteries

Activated carbon (AC) has been widely utilized as an active material in lithium-ion batteries (LIB) due to its stability and abundance. Nevertheless, the performance of AC anode materials alone falls short of competing with hybrid anode materials, which can attain maximum discharge capacity. Recently, a new two-dimensional (2D) transition metal carbide, MXene, has shown promising performance as an anode in LIB applications. The combination between AC and MXene has proved to improve battery performance previously. Thus, in this study, the electrode was prepared using a hybrid of activated carbon with vanadium carbide MXene (V₂C), which was synthesized by etching V₂AlC with in situ of hydrochloric acid (HCl) and lithium fluoride (LiF) at 90 °C for 30 min via microwave-assisted hydrothermal technique. The characterization by XRD pattern shows the appearance of V₂C MXene peak at 7.23°, indicating the successful etching from V₂AlC MAX. The as-prepared AC/V₂C_D at ratio 9:1 revealed excellent electrochemical properties as anode LIB, owned capacity up to 562 mAh g⁻¹ (at 50 mA g⁻¹) with cycling stability and columbic efficiency of 95.87 % and 98.2 %, respectively after 50 cycles. Moreover, AC/V₂C_D exhibited the smallest R_ct (18.50 Ω), and the discharge capacity of 370.25 mAh g⁻¹ was restored after 60 cycles when the current density returned to 50 mAg⁻¹, implying a good reversibility performance and high endurance for LIB. Furthermore, the fabricated full cell of AC/V₂C_D//LiFePO₄ exhibits initial discharge and charge capacity at 159.6 and 199.8 mAh g⁻¹, respectively, with 79.9 % of CE and delivers a stable cycling performance with reversible discharge specific capacity of 82.72 mAh g⁻¹ after 100 cycles. These promising results prove that the hybrid of AC/V₂C_D MXene can be good potential as an anode material in future LIBs applications.