材料科学
阳极
再分配(选举)
插层(化学)
离子
化学工程
动力学
扩散
电导率
异质结
储能
钛酸酯
化学物理
电极
无机化学
光电子学
复合材料
陶瓷
物理化学
热力学
化学
政治
量子力学
工程类
功率(物理)
有机化学
政治学
法学
物理
作者
Lan‐Fang Que,Fu‐Da Yu,Yang Xia,Liang Deng,Kokswee Goh,Chang Liu,Yunshan Jiang,Xu–Lei Sui,Zhen‐Bo Wang
出处
期刊:ACS Nano
[American Chemical Society]
日期:2020-10-07
卷期号:14 (10): 13765-13774
被引量:21
标识
DOI:10.1021/acsnano.0c05925
摘要
Sluggish kinetics and limited reversible capacity present two major challenges for layered titanates to achieve satisfactory sodium-ion storage performance at subzero-temperatures (subzero-T). To facilitate sodiation dynamics and improve reversible capacity, we proposed an additive-free anode with Sn(II) located between layers. Sn-5s in interlayer-confining Sn(II), which has a larger negative charge, will hybridize with O-2p to trigger charge redistribution, thereby enhancing electronic conductivity. H-titanates with an open framework are designed to stabilize Sn(II) and restrain subsequent volume expansion, which could potentially surpass the capacity limitation of titanate-based materials via a joint alloying–intercalation reaction with high reversibility. Moreover, the generation of conductive Na14Sn4 and the expansion of interlayer spacing resulting from the interlayered alloying reaction are beneficial for charge transfer. These effects synergistically endow the modified sample with a considerably lower activation energy and a 3-fold increase in diffusion. Consequently, the designed anode delivers excellent subzero-T adaptability when compared to the unmodified sample, maintaining capacity retention of 91% after 1200 cycles at −20 °C and 90% after 850 cycles at −30 °C.
科研通智能强力驱动
Strongly Powered by AbleSci AI