Sulfurized Polyacrylonitrile as a High-Performance and Low-Volume Change Anode for Robust Potassium Storage.
Sulfurized Polyacrylonitrile as a High-Performance and Low-Volume Change Anode for Robust Potassium Storage.
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DOI：
10.1021/acsnano.1c07990
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发表时间：
2021-10
期刊：
影响因子：
17.1
通讯作者：
L. Deng;Youran Hong;Yusi Yang;Juan Zhang;Xiaogang Niu;Jiangwei Wang;L. Zeng;W. Hao;Lin Gu
中科院分区：
文献类型：
--
作者：
L. Deng;Youran Hong;Yusi Yang;Juan Zhang;Xiaogang Niu;Jiangwei Wang;L. Zeng;W. Hao;Lin Gu
钾离子电池因其丰富的钾资源而被认为是一种低成本的电化学储能技术。然而，KIB的实际应用主要受到阳极材料的不令人满意的电化学性能的阻碍，所述阳极材料在钾化-脱钾过程中经常经历大的体积变化，限制了它们的循环寿命。在这里，低成本的硫化聚丙烯腈（S-PAN）被报道为一个有吸引力的候选阳极KIB。它提供了569 mAh g（S-PAN）-1的高钾存储容量，具有良好的倍率性能和循环稳定性（在1500次循环后没有容量损失，运行时间约188天）。详细的非原位光谱和原位微观表征表明，S-PAN优异的电化学性能归因于其共价C-S和S-S键的高可逆性，这些键在钾化-脱钾过程中经历重复的裂解-再二聚，伴随着相对较小的体积变化（小于24.2%）。随后，通过将高电压K2 MnFe（CN）6阴极与高容量S-PAN阳极配对构造的全电池展示了有吸引力的能量密度（290.9Wh kg-1）和长期循环稳定性（1200次循环，具有95.4%的容量保持率）。考虑到阳极和阴极材料的高性能和低成本，相信本全电池有望成为对成本敏感的电网规模应用的有竞争力的能量存储系统。
Potassium-ion batteries (KIBs) are considered as low-cost electrochemical energy storage technologies because of the abundant potassium resources. However, the practical applications of KIBs are mainly hampered by the unsatisfactory electrochemical performance of anode materials which often undergo large volume variations during potassiation-depotassiation, limiting their cycling life. Here, low-cost sulfurized polyacrylonitrile (S-PAN) is reported as an attractive anode candidate for KIBs. It provides a high potassium storage capacity of 569 mAh g(S-PAN)-1 with decent rate capability and cycling stability (no capacity loss after 1500 cycles, running time ∼188 days). Detailed ex situ spectroscopic and in situ microscopic characterizations reveal that the distinguished electrochemical performance of S-PAN is attributed to the high reversibility of its covalent C-S and S-S bonds which undergo repeated cleavage-redimerization during potassiation-depotassiation concomitant with relatively small volume variation (less than 24.2%). Subsequently, a full-cell constructed by pairing high-voltage K2MnFe(CN)6 cathode with high-capacity S-PAN anode demonstrates an attractive energy density (290.9 Wh kg-1) and long-term cycling stability (1200 cycles with 95.4% capacity retention). Given the high performance and low cost of both anode and cathode materials, it is believed that the present full-cell promises it as a competitive energy storage system for the cost-sensitive grid-scale applications.