fig4

Figure 4. Polysulfide adsorption effects studied by experiment and DFT calculations. (A) Polysulfide adsorption effect in the blank and N-AC added electrolytes. (A was photographed by the author, without any copyright concerns); (B) The geometries of perfect graphene and defect graphene with graphitic N, pyridinic N, and pyrrolic N; Configurations of Na₂S_x (x = 1, 2, 4, 6) adsorbed on pyridinic N-doped graphene layers (C) with annotation of C (gray), N (blue), S (yellow), Na (purple), and their corresponding adsorption energy (D); (E) The charge density difference of the short-chain Na₂S/graphene. Where yellow- and blue-distribution correspond charge accumulation and depletion, respectively; (F) The DOS of graphene and graphene doped with graphitic N, pyridinic N, and pyrrolic N. DOS: Density of states; TEGDME: tetraethylene glycol dimethyl ether; DFT: density functional theory.