Ordered Network of Interconnected SnO2 Nanoparticles for Excellent Lithium-Ion Storage
Ordered Network of Interconnected SnO2 Nanoparticles for Excellent Lithium-Ion Storage
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DOI：
10.1002/aenm.201401289
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发表时间：
2015-03-04
影响因子：
27.8
通讯作者：
Pol, Vilas G.
中科院分区：
文献类型：
--
作者：
Etacheri, Vinodkumar;Seisenbaeva, Gulaim A.;Pol, Vilas G.
通过固体醇盐前体的水解和热自组装，首次获得了具有独特3D结构和优异的锂离子（Li-ion）存储性能的互连氧化锡（SnO2）纳米粒子的有序网络。与无序纳米粒子和商业 SnO2 相比，由这些近似 9 nm 尺寸的 SnO2 粒子组成的介孔阳极表现出更高的比容量、倍率性能、库仑效率和循环稳定性。在0.1 C的电流密度下，放电容量达到778 mAh g(-1)，非常接近781 mAh g(-1)的理论极限。即使在2 C (1.5 A g(-1))和6 C (4.7 A g(-1))的高倍率下，这些有序SnO2纳米颗粒在放电后仍分别保持稳定的比容量为430和300 mAh g(-1)。 100 个循环。通过多次充放电过程循环，单个纳米颗粒之间的互连和 SnO2 电极的结构完整性得以保留。振实密度为1.60 g cm(-3)的有序SnO2纳米颗粒的电化学性能显着提高，这归因于优异的电极/电解质接触、锂离子扩散、不存在颗粒团聚以及改善的应变松弛（由于可用于局部膨胀的微小空间）。这项综合研究证明了介孔性和单个纳米粒子之间的互连对于提高 SnO2 阳极的锂离子存储电化学性能的必要性。
An ordered network of interconnected tin oxide (SnO2) nanoparticles with a unique 3D architecture and an excellent lithium-ion (Li-ion) storage performance is derived for the first time through hydrolysis and thermal self-assembly of the solid alkoxide precursor. Mesoporous anodes composed of these approximate to 9 nm-sized SnO2 particles exhibit substantially higher specific capacities, rate performance, coulombic efficiency, and cycling stabilities compared with disordered nanoparticles and commercial SnO2. A discharge capacity of 778 mAh g(-1), which is very close to the theoretical limit of 781 mAh g(-1), is achieved at a current density of 0.1 C. Even at high rates of 2 C (1.5 A g(-1)) and 6 C (4.7 A g(-1)), these ordered SnO2 nanoparticles retain stable specific capacities of 430 and 300 mAh g(-1), respectively, after 100 cycles. Interconnection between individual nanoparticles and structural integrity of the SnO2 electrodes are preserved through numerous charge-discharge process cycles. The significantly better electrochemical performance of ordered SnO2 nanoparticles with a tap density of 1.60 g cm(-3) is attributed to the superior electrode/electrolyte contact, Li-ion diffusion, absence of particle agglomeration, and improved strain relaxation (due to tiny space available for the local expansion). This comprehensive study demonstrates the necessity of mesoporosity and interconnection between individual nanoparticles for improving the Li-ion storage electrochemical performance of SnO2 anodes.