Dong Wen-Da, Li Chao-Fan, Wang Chun-Yu, Wu Liang, Hu Zhi-Yi, Liu Jing, Chen Li-Hua, Li Yu, Su Bao-Lian
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, 122 Luoshi Road, Wuhan, Hubei, 430070, China.
Nanostructure Research Centre (NRC), Wuhan University of Technology, 122 Luoshi Road, Wuhan, Hubei, 430070, China.
Small. 2022 Oct;18(43):e2105169. doi: 10.1002/smll.202105169. Epub 2021 Nov 28.
Sodium-ion batteries (SIBs) are considered as a promising large-scale energy storage system owing to the abundant and low-cost sodium resources. However, their practical application still needs to overcome some problems like slow redox kinetics and poor capacity retention rate. Here, a high-performance ZnSe/carbon fibers (ZnSe-CFs) anode is demonstrated with high electrons/Na transport efficiency for sodium-ion half/full batteries by engineering ZnSe/C heterostructure. The electrochemical behavior of the ZnSe-CFs heterostructure anode is deeply studied via in situ characterizations and theoretical calculations. Phase conversion is revealed to accelerate the "Zn-escape" effect for the formation of robust solid electrolyte interphase (SEI). This leads to the ZnSe-CFs delivering a superior rate performance of 206 mAh g at 1500 mA g for half battery and an initial discharge capacity of 197.4 mAh g at a current density of 1 A g for full battery. The work here heralds a promising strategy to synthesize advanced heterostructured anodes for SIBs, and provides the guidance for a better understanding of phase conversion anodes.
由于钠资源丰富且成本低廉，钠离子电池（SIBs）被认为是一种很有前景的大规模储能系统。然而，它们的实际应用仍需克服一些问题，如氧化还原动力学缓慢和容量保持率低等。在此，通过构建ZnSe/C异质结构，展示了一种用于钠离子半电池/全电池的具有高电子/钠传输效率的高性能ZnSe/碳纤维（ZnSe-CFs）负极。通过原位表征和理论计算深入研究了ZnSe-CFs异质结构负极的电化学行为。结果表明，相变加速了“锌脱出”效应，从而形成了坚固的固体电解质界面（SEI）。这使得ZnSe-CFs在半电池中以1500 mA g的电流密度下具有206 mAh g的优异倍率性能，在全电池中以1 A g的电流密度下具有197.4 mAh g的初始放电容量。本文的工作预示了一种合成用于SIBs的先进异质结构负极的有前景的策略，并为更好地理解相变负极提供了指导。
