Molecularly Imprinted Polymer Enables High-Efficiency Recognition and Trapping Lithium Polysulfides for Stable Lithium Sulfur Battery

• Published in: Nano letters Vol. 17; no. 8; pp. 5064 - 5070
• Main Authors: Liu, Jie, Qian, Tao, Wang, Mengfan, Liu, Xuejun, Xu, Na, You, Yizhou, Yan, Chenglin
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 09.08.2017
• Subjects: long-chain polysulfides; in situ UV/vis spectroscopy; Li2S nucleation test; lithium sulfur battery; Molecularly imprinted polymer
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.7b02332

Using molecularly imprinted polymer to recognize various target molecules emerges as a fascinating research field. Herein, we applied this strategy for the first time to efficiently recognize and trap long-chain polysulfides (Li2S x , x = 6–8) in lithium sulfur battery to minimize the polysulfide shuttling between anode and cathode, which enables us to achieve remarkable electrochemical performance including a high specific capacity of 1262 mAh g–1 at 0.2 C and superior capacity retention of over 82.5% after 400 cycles at 1 C. The outstanding performance is attributed to the significantly reduced concentration of long-chain polysulfides in electrolyte as evidenced by in situ UV/vis spectroscopy and Li2S nucleation tests, which were further confirmed by density functional theory calculations. The molecular imprinting is demonstrated as a promising approach to effectively prevent the free diffusion of long-chain polysulfides, providing a new avenue to efficiently recognize and trap lithium polysulfides for high-performance lithium sulfur battery with greatly suppressed shuttle effect.