fig5

Figure 5. (A) Cycling stability test of Li-S cells based on different separators at a rate of 2 C. (B) Rate performance of Li-S cells at different rates from 0.2 C to 5.0 C. (C) Cycling performance of Li-S cell using NbN/C@PP as separator with a high sulfur loading of 6.6 mg cm^-2 under a current density of 1 mA cm^-2. XPS spectra of the surface of cycled NbN/C@PP separator in (D) NbN 3d and (E) S 2p. SEM images of (F) lithium anode and (G and H) NbN/C@PP separator after cycling for 50 cycles.