Lei Tianyu, Xie Yiming, Wang Xianfu, Miao Shengyi, Xiong Jie, Yan Chenglin
State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China.
Soochow Institute for Energy and Materials Innovations (SIEMIS), College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215006, China.
Small. 2017 Oct;13(37). doi: 10.1002/smll.201701013. Epub 2017 Jul 27.
The rechargeable lithium-sulfur battery is recognized as a promising candidate for electrochemical energy storage system because of their exceptional advance in energy density. However, the fast capacity decay of sulfur cathode caused by polysulfide dissolution and low specific capacity caused by poor electrical conductivity still impede the further development of lithium-sulfur battery. To address above issues, this study reports the synthesis of feather duster-like TiO architecture by in situ growth of TiO nanowires on carbon cloth and further evaluates as sulfur host material. The strong chemical binding interaction between the polysulfides and TiO feather duster efficiently restrains the shuttle effect, leading to enhanced electrochemical kinetics. Besides, the in situ grown TiO NWs array also supply high surface for sulfur-loading and fast path for electron transfer and ion diffusion. As results, the novel CC/TiO /S composite cathode exhibits a high capacity of 608 mA h g at 1.0 C after 700 cycles corresponding to capacity decay as low as 0.045% per cycle with excellent Coulombic efficiency higher than 99.5%.
可充电锂硫电池因其在能量密度方面的卓越进展而被认为是电化学储能系统的一个有前途的候选者。然而，多硫化物溶解导致的硫阴极快速容量衰减以及电导率差导致的低比容量仍然阻碍着锂硫电池的进一步发展。为了解决上述问题，本研究报道了通过在碳布上原位生长TiO纳米线合成羽毛掸子状TiO结构，并进一步评估其作为硫宿主材料的性能。多硫化物与TiO羽毛掸子之间强烈的化学结合相互作用有效地抑制了穿梭效应，从而增强了电化学动力学。此外，原位生长的TiO纳米线阵列还为硫负载提供了高表面积，并为电子转移和离子扩散提供了快速通道。结果，新型CC/TiO/S复合阴极在1.0 C下经过700次循环后表现出608 mA h g的高容量，对应于每循环低至0.045%的容量衰减，库仑效率高于99.5%。
