Electrostatic Self‐Assembly of CoSe 2 HBs/Ti 3 C 2 T x Composites for Long‐cycle‐life Sodium Ion Batteries
Electrostatic Self‐Assembly of CoSe 2 HBs/Ti 3 C 2 T x Composites for Long‐cycle‐life Sodium Ion Batteries
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DOI：
10.1002/celc.202100802
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发表时间：
2021-09
期刊：
影响因子：
4
通讯作者：
Li Zhang;Weizhe Liu;Quanhu Ma;Yongtai Xu;Ziqiang Liu;Gaowei Wang
中科院分区：
文献类型：
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作者：
Li Zhang;Weizhe Liu;Quanhu Ma;Yongtai Xu;Ziqiang Liu;Gaowei Wang
钠离子蓄电池（SIBs）以其低成本和高能量/功率密度而被认为是最有前途的储能装置之一。然而，有限的循环寿命和可选择的材料的差的倍率性能限制了它们的全球应用。为了在纳米尺度上调控材料的结构，减小体积膨胀和提高本征电导率是解决这些问题的两个积极策略。本文基于静电自组装原理设计并制备了CoSe 2空心盒/Ti 3C 2 Tx薄片复合材料（CoSe 2 HBS/Ti 3C 2 Tx）。得益于结构和成分的优势，Ti 3C 2 Tx的高导电性和大层间距结构与CoSe 2的高容量之间存在协同效应。CoSe 2 HBs/Ti 3C 2 Tx复合材料表现出优异的倍率性能（在50、100、200、500、1000和2000 mA g-1的电流密度下，CoSe 2 HBs/Ti 3C 2 Tx的平均比容量分别为225.8、210.5、194.6、169.9、153.2和135.8 mAh g-1，并且当电流密度变回小值时，其可以迅速呈现可逆容量，在100 mA g-1下为199.1 mAh g-1）、优异的循环寿命（3000次循环）和超过100%的高库仑效率。 这种复合材料可以被认为是另一种有前途的候选人，高性能的能量存储设备。
Sodium ion batteries (SIBs) are considered as one of the most promising energy storage devices owing to lower cost and higher energy/power density. However, limited cycling life and poor rate capability of selectable materials restrict their worldwide application. To regulate the material's structure at the nanoscale, reducing volume expansion and increasing the intrinsic conductivity are two positive strategies to deal with these issues. Herein, CoSe2Hollow Boxes/Ti3C2Txflakes composites (CoSe2HBs/Ti3C2Tx) is designed and fabricated based on electrostatic self‐assembly. Benefitting from the structural and compositional advantages, synergistic effects between the high conductivity and large layer spacing structure of Ti3C2Txand the high capacity CoSe2is observed. The CoSe2HBs/Ti3C2Txcomposites exhibit excellent rate capability (Average specific capacities of CoSe2HBs/Ti3C2Txare 225.8, 210.5, 194.6, 169.9, 153.2, and 135.8 mAh g−1at current densities of 50, 100, 200, 500, 1000 and 2000 mA g−1, respectively, and it could rapidly assume a reversible capacity when the current density changed back to small value, 199.1 mAh g−1at 100 mA g−1), exceptional cycling life (3000 cycles), and ∼100 % high coulombic efficiency. Such composites can be considered as another promising candidate for high performance energy storage devices.