Polypeptoidmaterial as an anchoring material for Li-S batteries

Abstract

Nowadays, lithium−sulfur (Li−S) batteries have attracted considerable attention as a potential candidate for next-generation rechargeable batteries due to their high theoretical specific energy and environmental friendliness. One of the main problems with Li−S batteries is that the lithium polysulfides (LiPSs) easily decompose in the electrolyte which is known as the shuttle effect. Recently, the polypeptoid nanosheet crystal structure has been experimentally synthesized which is very useful for tremendous advances in soft material imaging as well as enabling to design biomimetic nanomaterials. Due to the very interesting properties of the polypeptoid material, we have investigated the electronic structure and charge-transfer mechanism for the lithium−sulfur batteries for the cathode material. The calculated adsorption energies of LiPSs on the surface of the polypeptoid material are in the range of −4.41 to −4.64 and −0.91 eV for the sulfur clusters. Also, the adsorption energies between the interaction of LiPSs and electrolytes (DME and DOL) are 0.75−0.89 eV. It means that the polypeptoid material could suppress the shuttle effect of LiPSs and significantly enhance the cycling performance of Li−S batteries. From these investigated results, the polypeptoid material will be a promising anchoring material for Li−S batteries.