fig4

Figure 4. (A) The first five CV curves of the cell with C/CoFe-MXene electrode; (B) Rate capability of different electrodes and (C) galvanostatic charge/discharge profiles of the cell with C/CoFe-MXene electrode at different rates; (D) Cycling performance of the cell with different electrodes under 1 C; (E) Galvanostatic charge/discharge profiles of the cell at the 1^st and the 700^th cycle under 1 C; (F) Nyquist plots after cycling at 1 C; (G) Ultralong-term cycling performance of C/CoFe-MXene electrode at 5 C; (H) Cycling performance of C/CoFe-MXene/S with high sulfur loading at 0.5 C and inset digital photo of a light-emitting diode (LED) powered by the cell. CV: Cyclic voltammetry.