3D Graphene Decorated NaTi2(PO4)3 Microspheres as a Superior High-Rate and Ultracycle-Stable Anode Material for Sodium Ion Batteries
3D Graphene Decorated NaTi2(PO4)3 Microspheres as a Superior High-Rate and Ultracycle-Stable Anode Material for Sodium Ion Batteries
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3D 石墨烯装饰的 NaTi2(PO4)(3) 微球作为钠离子电池的优质高倍率和超循环稳定阳极材料
DOI：
10.1002/aenm.201502197
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发表时间：
2016-10-12
影响因子：
27.8
通讯作者：
Yang, Hanxi
中科院分区：
文献类型：
--
作者：
Fang, Yongjin;Xiao, Lifen;Yang, Hanxi
DOI：10.1002/aenm. 201502197由于钠化/去钠化过程中体积变化大而导致循环性能差。因此，有必要开发具有高功率容量、长循环寿命和良好安全性的SIB。最近，具有NASICON结构的NaTi 2（PO 4）3作为一种有前途的阳极材料受到越来越多的关注，这是由于“零应力”框架提供了长期循环稳定性，高Na离子电导率保证了优异的倍率性能，大的理论容量（133 mAh g− 1），低成本和更好的安全特性。[22-25]然而，磷酸盐骨架具有固有的低电子电导率，限制了其在具有高功率性能的SIB中的应用。[11-13，22，25] Demas等首次报道了NaTi 2（PO 4）3在有机电解质中的可逆钠化反应，发现另外两个钠离子可以通过两相机理可逆插层，得到Na 3 Ti 2（PO 4）3产物。[38]同时，多个研究小组对该化合物的电化学转变进行了详细的结构解析。[39后来，已经进行了许多努力来通过导电碳涂层和纳米结构化NaTi 2（PO 4）3颗粒来改善其电化学性能。[22 41-46]例如，Wu等人报道了NaTi 2（PO 4）3/石墨烯电极，其具有高达50 C的上级倍率性能。[22]Yang等人已经合成了碳和TiO 2涂层的NaTi 2（PO 4）3纳米立方体复合材料，该复合材料能够实现高倍率性能（83.5 mAh g− 1，在100 ℃）和长期循环性能。[47]从实际电池应用的观点来看，期望NaTi 2（PO 4）3纳米颗粒不仅具有高功率性能，而且还具有高振实密度，从而能够实现足够高的能量密度。为了实现高倍率性能和稳定的循环性能，一个有效的策略是将纳米NaTi 2（PO 4）3颗粒嵌入高导电性碳框架中。在这样的纳米结构中，纳米颗粒能够缩短钠离子和电子的传输距离，并提供丰富的反应界面，而碳基质在NaTi 2（PO 4）3颗粒之间形成电子布线路径，从而增加电导率，并且还用作坚固且灵活的缓冲器，以适应与放电期间重复的Na离子插入/抽出相关的体积变化。充电周期二维石墨烯片由于其上级导电性、高表面积和机械强度而成为广泛应用于电池材料应用中的理想导电基质。[14此外，对于实际应用，重要的是使用具有大尺寸颗粒的电极材料以增加体积能量密度。在此，我们报道了一种简便的喷雾干燥方法，以解决对全球能源供应的日益关注，刺激了用于电动汽车、智能电网和可再生发电站的快速可充电、长期耐用、高容量和低成本储能技术的发展。尽管锂离子电池（LIB）现在被广泛研究作为用于这种能量存储应用的有吸引力的技术之一，但是它们遭受高成本和锂资源的有限可用性。[1-3]为了寻找LIB的竞争性替代品，近年来由于钠资源的低成本和广泛可用性，钠离子电池（SIB）已被积极重新审视。[4]然而，由于钠离子的离子半径较大，且在刚性无机晶格中结合力较强，因此寻找合适的钠主体仍然是一个艰巨的挑战..
DOI: 10.1002/aenm. 201502197 from poor cycling performance due to large volume change during sodiation/desodiation processes. Therefore, it is necessary to develop SIBs with high power capability, long cycle life and good safety. Recently, NaTi 2 (PO 4) 3 with a NASICON structure has received increasing attention as a promising anode material due to “zero-stress” framework proving long-term cycling stability, high Na-ion conductivity guaranteeing excellent rate capability, large theoretical capacity (133 mAh g− 1), low cost and much better safety characteristics.[22–25] However, the phosphate framework possesses inherent low electronic conductivity to restrict its application in SIBs with high-power performance.[11–13, 22, 25] Demas et al. first reported the reversible sodiation of NaTi 2 (PO 4) 3 in organic electrolyte and found that two additional sodium ions could be reversibly intercalated via a two-phase mechanism to obtain the Na 3Ti 2 (PO 4) 3 product.[38] At the same time, a number of research groups conducted detailed structure elucidation for the electrochemical transition of this compound.[39, 40] Later on, numerous efforts have been done to improve its electrochemical performance, by conductive carbon coating and nanoarchitecturing the NaTi 2 (PO 4) 3 particles.[22, 41–46] For example, Wu et al. reported a NaTi 2 (PO 4) 3/graphene electrode with superior rate capability up to 50 C rate.[22] Yang et al. have synthesized carbon and TiO 2 coated NaTi 2 (PO 4) 3 nanocube composites, which enable high-rate capability (83.5 mAh g− 1 at≈ 10 C) with long-term cyclability.[47] In the viewpoint of practical battery application, it is desirable for the NaTi 2 (PO 4) 3 nanoparticles not only to have high-power performance but also to possess high tap density, thus enabling sufficiently high energy density. To achieve both high rate capability and stable cycling performance, an effective strategy is to embed nanosized NaTi 2 (PO 4) 3 particles in highly conductive carbon frameworks. In such a nanoarchitecture, the nanoparticles are able to shorten transport distance of sodium ions and electrons and also provide abundant reaction interface, while the carbon matrix forms an electronic wiring pathways among the NaTi 2 (PO 4) 3 particles thus to increase the conductivity and also function as a robust and flexible buffer to accommodate volume changes associated with repeated Na-ion insertion/extraction during discharging/charging cycles. 2D graphene sheets appear to be an ideal conductive matrix widely used in battery material application, owning to its superior electrical conductivity, high surface area, and mechanical robustness.[14, 18, 22, 32, 33, 44] Besides, for practical application, it is important to use the electrode materials with large-sized particles to increase the volumetric energy density. Herein, we reported a facile spray-drying method to prepareGrowing concerns about global energy supply have stimulated the development of fast rechargeable, long-durable, highcapacity, and low-cost energy storage technologies for electric vehicles, smart grids, and renewable power stations. Although lithium ion batteries (LIBs) are now extensively investigated as one of attractive technologies for such energy storage applications, they suffer from high cost and limited availability of lithium resources.[1–3] To search for a competitive alternative to LIBs, sodium ion batteries (SIBs) have been actively revisited in recent years due to the low cost and wide availability of sodium resources.[4] However, because of the larger ionic radius of sodium ions and their strong binding in the rigid inorganic lattices, it is still an arduous challenge to find suitable Na-host …