Energy Material Advances / 2021 / Article / Fig 2

Research Article

3-D Edge-Oriented Electrocatalytic NiCo2S4 Nanoflakes on Vertical Graphene for Li-S Batteries

Figure 2

(a) CV curves of LSB cells with different overlayers incorporated in the cathode. (b) UV-Vis absorption spectra of Li2S6 solution after being soaked with different layers (inset is the photograph showing the solution color difference after soaking). (c) High-resolution XPS spectrum of Ni 2p of NCS after Li2S6 absorption. (d) EIS Nyquist plots of fresh cells with different overlayers incorporated in the cathode (sulfur loading: 2 mg·cm−2; inset: the equivalent circuit for modeling). (e) The derived three resistance values in the equivalent circuit of (d). (f) CV curves recorded on the NCS/EOG/CNF cell under different scan rates. (g) The plots of peak current density versus square root of the scan rate for the redox reactions. (h) Schematic illustration of the function of NCS/EOG/CNF catalytic overlayer in accelerating LiPSs conversion processes.