Jo Hakrae, Cho Youngseul, Yoo Taehyun, Jeon Youngmoo, Hong Hwichan, Piao Yuanzhe
Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, 145 Gwanggyo-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16229, Republic of Korea.
Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, 145 Gwanggyo-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-270, Republic of Korea.
ACS Appl Mater Interfaces. 2021 Oct 13;13(40):47593-47602. doi: 10.1021/acsami.1c12855. Epub 2021 Sep 29.
Recent studies of lithium-sulfur (Li-S) batteries have identified that a modified separator plays a critical role in challenging the capacity fading and shuttle effect of lithium polysulfides (LiPSs). Herein, we report a polyaniline-encapsulated hollow Co-Fe Prussian blue analogue (CFP@PANI) for separator modification. The open frame-like hollow CFP was synthesized via oriented attachment (OA). To improve the catalytic effect and electrical conductivity, PANI was coated on the synthesized CFP. The resulting CFP@PANI was applied on the conventional polypropylene (PP) separator (CFP@PANI-PP) with vacuum filtration. With a ketjen black/sulfur (KB/S) cathode with 66% of the sulfur load, the CFP@PANI-PP exhibited an initial capacity of 723.1 mAh g at a current density of 1 A g. Furthermore, the CFP@PANI-PP showed stable cycling performance with 83.5% capacity retention after 100 cycles at 1 A g. During the 100 cycles, each cycle maintained high coulombic efficiency above 99.5%, which indicates that the CFP@PANI-PP could inhibit LiPS migration to the anode side without a Li transport disturbance across the separator. Overall, the CFP@PANI-PP efficiently suppressed LiPSs, resulting in enhanced electrochemical performance. The current study provides useful insight into designing a nanostructure for separator modification of Li-S batteries.
近期对锂硫（Li-S）电池的研究表明，改性隔膜对于应对多硫化锂（LiPSs）的容量衰减和穿梭效应起着关键作用。在此，我们报道一种用于隔膜改性的聚苯胺包覆的中空钴铁普鲁士蓝类似物（CFP@PANI）。通过定向附着（OA）合成了开放框架状的中空CFP。为提高催化效果和电导率，在合成的CFP上包覆了PANI。通过真空过滤将所得的CFP@PANI应用于传统聚丙烯（PP）隔膜（CFP@PANI-PP）。对于硫负载量为66%的科琴黑/硫（KB/S）阴极，CFP@PANI-PP在1 A g的电流密度下表现出723.1 mAh g的初始容量。此外，CFP@PANI-PP在1 A g下循环100次后容量保持率为83.5%，显示出稳定的循环性能。在这100次循环中，每次循环的库仑效率均保持在99.5%以上，这表明CFP@PANI-PP可以抑制LiPS向阳极侧迁移，同时不会干扰锂在隔膜中的传输。总体而言，CFP@PANI-PP有效抑制了LiPSs，从而提高了电化学性能。当前的研究为设计用于Li-S电池隔膜改性的纳米结构提供了有益的见解。
