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Integrating porous materials, especially, metal organic frameworks (MOFs) as anchoring components on cathode surfaces enhances sulfur–based battery performance due to strong polysulfide anchoring affinity. This study employs a thermodynamically stable ZIF–8 cluster to improve the electrochemical behavior of calcium–sulfur (Ca─S) batteries by trapping polysulfides (PS), including α–S 8 , CaS 8 , CaS 6 , CaS 4 , CaS 2 , and CaS, within its hexagonal window. The computationally efficient ZIF–8 cluster confirms effective PS adsorption, with energies ranging from –0.75 to –4.94 eV for α–S 8 through CaS. Projected density of states analysis reveals Ca─N interactions for higher–order PS, while lower–order PS exhibit strong C─S bonds. Bader charge and charge density difference analyses reveal charge accumulation on sulfur atom in CaS and charge depletion on the carbon atom of the 2‐methylimidazolate ligand involved in C─S bonding. The calculated Gibbs free energy change of 0.74 eV for the transition of CaS 4 to CaS 2 identifies this as the rate‐limiting step in the sulfur reduction pathway. Furthermore, the relatively low adsorption energies (≤ –1 eV) of PS in the selected electrolyte environment suggest that dissolution of higher‐order PS into the electrolyte during discharge is unlikely, supporting improved electrochemical stability.
S. et al. (Mon,) studied this question.