On the role of oxidized graphene interfaces in lithium sulfur batteries: Thermodynamic and kinetic aspects using density functional theory

Constructing a multifunctional mesoporous composite of metallic cobalt nanoparticles and nitrogen‐doped reduced graphene oxides for high‐performance lithium–sulfur batteries

“…The peak-fitted four signals in the high-resolution C 1s XPS spectrum of Co/NrGO at 278.4, 285.0, 285.5, and 291.2 eV, can be assigned to the presence of C─C/C═C, C-N, C-N, C═N bonds, and O═C─O − functional groups, respectively (Figure 3D). 46 As reported in various studies, 14,[47][48][49][50] [50][51][52] Importantly, due to the doping of metallic Co nanoparticles, pristine Co/NrGO acquires a much higher electronic conductivity (32.36 S cm −1 ) than its Co-absent counterpart NrGO (4.48 S cm −1 ).…”

“…The peak‐fitted four signals in the high‐resolution C 1s XPS spectrum of Co/NrGO at 278.4, 285.0, 285.5, and 291.2 eV, can be assigned to the presence of C─C/C═C, C–N, C–N, C═N bonds, and O═C─O − functional groups, respectively (Figure 3D). 46 As reported in various studies, 14,47–50 nitrogen doping of a nanostructured carbon can significantly improve its surface interactions with the electrolyte‐soluble intermediate Li 2 S n of cycled Li–S batteries, facilitating catalysis of the embedded Co nanoparticles for the efficient redox reactions of polysulfide Li 2 S n . The spectra of pyridinic─N (398.7 eV), Co─N (399.5 eV), pyrrolic─N (400.5 eV), and graphitic─N (401.6 eV) of Co/NrGO are fitted out and marked in Figure 3E, and the Co─N species may functionalize in confining the catalytic centers (i.e., metallic nanoparticles) within the conductivity‐enhanced carbonaceous network.…”

“…One of the well‐developed carbonaceous materials used in Li–S batteries is graphene, which possesses high electrical conductivity, large surface area, and excellent mechanical strength to load or to immobilize S‐based species 11–14 . However, the weak host–guest interactions between nonpolar graphene and polar guests can hardly be associated with the entrapment of intermediate Li 2 S n 15–17 .…”

“…9,10 One of the well-developed carbonaceous materials used in Li-S batteries is graphene, which possesses high electrical conductivity, large surface area, and excellent mechanical strength to load or to immobilize S-based species. [11][12][13][14] However, the weak host-guest interactions between nonpolar graphene and polar guests can hardly be associated with the entrapment of intermediate Li 2 S n . [15][16][17] Therefore, on the one hand, heteroatom-doped graphene-based materials are tentatively used to enhance the chemical entrapment of Li 2 S n , [18][19][20] and on the other hand, introduction of metalbased active centers into the graphene-based frameworks of the sulfur cathode may yield an unexpected catalytic ability to improve the kinetics of polysulfide conversion.…”

Understanding the interactions between lithium polysulfides and anchoring materials in advanced lithium–sulfur batteries using density functional theory

“…Similar results were found for the LiPSs interactions with oxidized graphene layers containing functional groups (hydroxyl, epoxy, and carboxyl groups). 89,90…”