Bai Yu-Lin, Liu Yu-Si, Ma Chao, Wang Kai-Xue, Chen Jie-Sheng
Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering , Shanghai Jiao Tong University , Shanghai 200240 , P. R. China.
ACS Nano. 2018 Nov 27;12(11):11503-11510. doi: 10.1021/acsnano.8b06585. Epub 2018 Oct 16.
Sodium-ion batteries (SIBs) are generally considered as promising cheap alternatives of lithium-ion batteries for stationary renewable energy storage and have received increasing attention in recent years. The exploration of anode materials with efficient electron transportation is essential for improving the performance of SIBs. Inspired by the signal transfer mode of a neuron, we designed a composite by stringing MoS nanoflower (soma) with multiwall carbon nanotubes (MWCNTs) (axons). High-resolution TEM observation reveals a lattice matching growth mechanism of MoS nanosheets on the interface of MWCNTs and the lattice expansion of the (002) plane of MoS. The lattice matching among the MoS nanosheet and MWCNT could facilitate electron transfer and structure maintenance upon cycling. The expanded distance of the (002) plane of MoS would also promote the sodium-ion intercalation/deintercalation kinetics of the composite. Benefiting from the structural features, when used as an anode material for SIBs, the composite exhibits excellent electrochemical performance, including high specific capacity, excellent cycle stability, and superior rate capabilities. A stable capacity of 527.7 mAh g can be achieved after 110 cycles at a current density of 100 mA g. The neuron-inspired design proposed is a promising and efficient strategy for the development of electrode materials for SIBs with high mass transport kinetics and structural stability.
钠离子电池(SIBs)通常被认为是用于固定式可再生能源存储的锂离子电池有前景的廉价替代品,并且近年来受到了越来越多的关注。探索具有高效电子传输的负极材料对于提高SIBs的性能至关重要。受神经元信号传递模式的启发,我们通过将MoS纳米花(细胞体)与多壁碳纳米管(MWCNTs,轴突)串连设计了一种复合材料。高分辨率透射电子显微镜观察揭示了MoS纳米片在MWCNTs界面上的晶格匹配生长机制以及MoS(002)面的晶格膨胀。MoS纳米片与MWCNT之间的晶格匹配可以促进循环过程中的电子转移和结构维持。MoS(002)面扩展的间距也将促进复合材料的钠离子嵌入/脱嵌动力学。受益于这些结构特征,当用作SIBs的负极材料时,该复合材料表现出优异的电化学性能,包括高比容量、出色的循环稳定性和卓越的倍率性能。在100 mA g的电流密度下循环110次后,可实现527.7 mAh g的稳定容量。所提出的受神经元启发的设计是开发具有高质量传输动力学和结构稳定性的SIBs电极材料的一种有前景且高效的策略。