Using the first-principle calculations, we have investigated the chemical properties of small lithium clusters adsorbed on Stone−Wales defected graphene (SW-GN) sheet. The DFT study shows that the Li clusters orient above the defect region in the SW-GN sheet. A single SW defect could accommodate a maximum of four Li atoms. The interaction energy shows that the presence of the SW defect in the graphene sheet enhances the interaction between the SW-GN sheet and Li clusters. As the cluster size increases, the interaction between the defective sheet and Li clusters increases. The interaction energy and cohesive energy per Li atom show a decrease in energy value as the Li cluster size increases, and this result is substantiated with adsorption capacity value. The charge transfer indicates that SW defected graphene acts as an electron acceptor while the clusters behave as donors. The DOS plot indicates that the adsorption of Li clusters has influenced a change in the electronic property of the bare SW graphene sheet, thereby shifting the Fermi level to the conduction band. From all the above results, we infer that SW defected graphene proves to be a prospective anode material by reducing the clustering of Li atoms, thereby hindering dendrite formation. Further improvement in the anodic material could be established through an increase in the defect ratio in the graphene sheet.

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Lithium‐Sulfur (Li−S) batteries have become an undoubtful choice for future high‐energy applications due to their high theoretical capacity and energy density. However, the “Shuttle Effect” is a phenomenon that hinders the practical application of Li−S batteries. The present work reports a facile synthesis of poly(phthalazinone ether sulfone ketones) (PPESK) as a surface modifier for the conventional glass fiber separator to arrest the shuttle effect. PPESK is prepared by aromatic nucleophilic substitution (SNAr) with 4‐(4‐hydroxyphenyl) phthalazin‐1(2H)‐one, bis (4‐chlorophenyl methanone), and 4,4′‐sulfinyl‐bis (chlorobenzene). The Li−S cells with PPESK@GF separators deliver a high initial discharge capacity of 1054.2 mAh g−1 at 0.2 C than GF (991.5 mAh g−1 at 0.2 C). Density functional theory (DFT) calculations are performed to determine the interaction between the PPESK with lithium polysulfides, Li2Sn (n=1, 2, 4, 6, and 8). The results indicate that all the lithium polysulfides strongly bind with the sulfone nitrogen site of the PPESK structure with high binding energy, particularly Li2S6 has −492.58 kcal/mol. The atoms‐in‐molecules analysis (AIM) shows the presence of ionic bonds between PPESK and lithium polysulfides. Gibb's free energy, the thermodynamical parameter, indicates that the reaction is exergonic and spontaneous. Overall, the theoretical findings augment the observed experimental results.

Given the potential availability, non-toxicity, and environmental acceptability of alternatives to lithium-ion batteries (LIBs), secondary batteries utilizing magnesium (Mg) ions have garnered significant attention. Numerous recent studies have focused on identifying suitable anode materials for post-lithium-ion batteries, particularly magnesium-ion batteries. In this context, we conducted a theoretical investigation using density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations to examine the 2D multiphase (1T/2H-MoS2) anode material. Our observations confirmed the efficacy of this material as an anode. The results highlight its exceptional stability, high binding energy, enhanced metallic characteristics following Mg adsorption, theoretical specific capacity, and remarkably low diffusion barriers. Notably, the anode material exhibits an ultralow energy barrier of 0.05 eV, surpassing that of extensively studied 2D materials. By employing a wide range of Mg2+ concentration during the charging process, we achieved a high specific capacity of 1339 mAh g− 1 ions, coupled with an average operating voltage of 0.13 V. These findings provide valuable insights for the experimental design of exceptional anode materials.