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2019_EJRNL_PP_Vang_do_2.pdf
PUBLIC Latifa Noor

Lithium?sulfur (Li?S) batteries are attractingsubstantial attention because of their high-energy densitiesand potential applications in portable electronics. However, anintrinsic property of Li?S systems, that is, the solubility oflithium polysulfides (LiPSs), hinders the commercialization ofLi?S batteries. Herein, a new material, that is, carbon nitridephosphorus (CNP), is designed and synthesized as a superiorLiPS adsorbent to overcome the issues of Li?S batteries. Boththe experimental results and the density functional theory(DFT) calculations confirm that CNP possesses the highestbinding energy with LiPS at a P concentration of?22% (CNP22). The DFT calculations explain the simultaneous existence ofLi?N bonding and P?S coordination in the sulfur cathode when CNP22 interacts with LiPS. By introducing CNP22 into theLi?S systems, a sufficient charging capacity at a low cutoffvoltage, that is, 2.45 V, is effectively implemented, to minimize theside reactions, and therefore, to prolong the cycling life of Li?S systems. After 700 cycles, a Li?S cell with CNP22 gives a highdischarge capacity of 850 mA h g?1and a cycling stability with a decay rate of 0.041% cycle?1. The incorporation of CNP22 canachieve high performance in Li?S batteries without concerns regarding the LiPS shuttling phenomenon.