Ordered SnO nanoparticles in MWCNT as a functional host material for high-rate lithium-sulfur battery cathode
Ordered SnO nanoparticles in MWCNT as a functional host material for high-rate lithium-sulfur battery cathode
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DOI：
10.1007/s12274-016-1397-y
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发表时间：
2017-01
期刊：
影响因子：
9.9
通讯作者：
A. Kim;Min Kyu Kim;Ji Young Kim;Yuren Wen;L. Gu;Van-Duong Dao;Ho-Suk Choi;D. Byun;Joong-Kee Lee-Jo
中科院分区：
文献类型：
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作者：
A. Kim;Min Kyu Kim;Ji Young Kim;Yuren Wen;L. Gu;Van-Duong Dao;Ho-Suk Choi;D. Byun;Joong-Kee Lee-Jo
锂硫电池已成为下一代电池最有前途的候选电池之一，但由于硫电导率低、体积膨胀大、多硫化物穿梭严重等原因，其发展仍受到限制。在此，我们提出了一种新的混合电极与三元纳米材料的基础上硫浸渍的多壁碳纳米管填充有序的一氧化锡纳米粒子（MWCNT-SnO/S）。使用干等离子体还原方法，制备机械坚固的材料作为锂硫电池的阴极主体材料。MWCNT-SnO/S电极具有较高的电导率、较好的多硫化物捕获能力以及在反复充放电过程中较小的体积变化，原位透射电子显微镜和紫外-可见吸收光谱结果表明MWCNT-SnO主体有效地抑制了锂化过程中的体积膨胀，减少了多硫化物向电解液中的溶解.此外，有序的SnO纳米粒子在多壁碳纳米管促进快速离子/电子转移的氧化还原反应过程中，作为连接的多壁碳纳米管的壁之间的连接。具有70 wt.%的高硫含量的MWCNT-SnO/S阴极在167.5 mA·g-1（0.1 C倍率）下，其首次放电容量为1682.4 mAh·g-1，在0.5 C下，经1,000次循环后，容量保持在530.1 mAh·g-1，库仑效率接近100%。此外，即使在20 ℃的高电流速率下，该电极也表现出高容量。
Lithium-sulfur battery has become one of the most promising candidates for next generation batteries, and it is still restricted due to the low sulfur conductivity, large volume expansion and severe polysulfide shuttling. Herein, we present a novel hybrid electrode with a ternary nanomaterial based on sulfur-impregnated multiwalled carbon nanotubes filled with ordered tin-monoxide nanoparticles (MWCNT-SnO/S). Using a dry plasma reduction method, a mechanically robust material is prepared as a cathode host material for lithium-sulfur batteries. The MWCNT-SnO/S electrode exhibits high conductivity, good ability to capture polysulfides, and small volume change during a repeated charge–discharge process.In situtransmission electron microscopy and ultraviolet–visible absorption results indicate that the MWCNT-SnO host efficiently suppresses volume expansion during lithiation and reduces polysulfide dissolution into the electrolyte. Furthermore, the ordered SnO nanoparticles in the MWCNTs facilitate fast ion/electron transfer during the redox reactions by acting as connective links between the walls of the MWCNTs. The MWCNT-SnO/S cathode with a high sulfur content of 70 wt.% exhibits an initial discharge capacity of 1,682.4 mAh·g–1at 167.5 mA·g–1(0.1 C rate) and retains a capacity of 530.1 mAh·g–1at 0.5 C after 1,000 cycles with nearly 100% Coulombic efficiency. Furthermore, the electrode exhibits the high capacity even at a high current rate of 20 C.