Synthesis, structure, and electrochemical properties of O 0 3-type monoclinic NaNi0.8Co0.15Al0.05O2 cathode materials for sodium- ion batteries
Synthesis, structure, and electrochemical properties of O 0 3-type monoclinic NaNi0.8Co0.15Al0.05O2 cathode materials for sodium- ion batteries
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O 0 3 型单斜晶系NaNi0.8Co0.15Al0.05O2钠离子电池正极材料的合成、结构及电化学性能
DOI：
10.1039/c8ta07842d
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发表时间：
2019
影响因子：
11.9
通讯作者：
Zhuo Shuping
中科院分区：
文献类型：
--
作者：
Zhou Pengfei;Liu Xiaolan;Weng Junying;Wang Li;Wu Xiaozhong;Miao Zhichao;Zhao Jinping;Zhou Jin;Zhuo Shuping
钠离子电池（SIBs）由于其丰富的低成本钠和与商用锂离子电池相似的电化学机制，在固定储能方面显示出巨大的前景。o3型层状纳米二氧化钛被认为是极具发展前景的sib正极材料之一。然而，它的相变不可逆，动力学缓慢，量产技术落后，导致容量衰减快，速率性能差，实际应用有限。本文采用可扩展共沉淀法和高温煅烧工艺合成了单斜相结构的新型O ' 3型层状NaNi0.8Co0.15Al0.05O2。以离子半径相近、价态相同的Co3+和Al3+取代Ni3+，增强了结构的稳定性，提高了（脱）钠化过程中相变的可逆性。微球的层次化结构和原生纳米晶体的组装，可以为钠离子/电子的传递提供高的压实密度和短的扩散路径。由于这些优越的优点，单斜纳米0.8 co0.15 al0.05 o2微球具有153.9 mA h g−1的初始可逆容量，在0.1C下库仑效率为89.1%，在1C下循环200次后容量保持率为86.7%，有望成为SIB应用的高容量和稳定的阴极材料。
Sodium-ion batteries (SIBs) have shown great promise in stationary energy storage due to the abundance of low-cost sodium and the similar electrochemical mechanism to that of commercial lithium-ion batteries. O3-type layered NaNiO2 is considered as one of the most promising cathode materials for SIBs. However, it suffers from irreversible phase transitions, sluggish kinetics and poor mass-production techniques, incurring rapid capacity fading, poor rate performance and limited practical applications. Herein, a novel O′3-type layered NaNi0.8Co0.15Al0.05O2 with a monoclinic phase structure is synthesized by a scalable co-precipitation method followed by a high-temperature calcination process. The substitution of similar ionic radii and same valence Co3+ and Al3+ for Ni3+ enhances the structural stability and improves the reversibility of phase transitions during (de)sodiation processes. The hierarchical architecture of microspheres and assembling of primary nanocrystals, can provide high compacted density and supply short diffusion paths for sodium ion/electron transport simultaneously. Because of these superior merits, the monoclinic NaNi0.8Co0.15Al0.05O2 microspheres exhibit an initial reversible capacity of 153.9 mA h g−1 with a coulombic efficiency of 89.1% at 0.1C and remarkable capacity retention of 86.7% after 200 cycles at 1C, potentially serving as a high capacity and stable cathode material for SIB applications.