A stable layered P3/P2 and spinel intergrowth nanocomposite as a long-life and high-rate cathode for sodium-ion batteries. Issue 14 (27th March 2018)

• Record Type: Journal Article
• Authors: Hou, Peiyu; Yin, Jiangmei; Lu, Xianhang; Li, Jiaming; Zhao, Yue; Xu, Xijin
• Is Part Of: Nanoscale. Volume 10:Issue 14(2018)
• Page Start: 6671
• Page End: 6677
• Publication Date: 2018-03-27
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c8nr00650d
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : A stable layered P2/P3 and Fd 3̄ m spinel intergrowth composite is rationally designed, and the triphase synergy in this layered/spinel hybrid cathode is also demonstrated in half-cells and full-cells. Abstract : Layered sodium transition-metal oxides, Na x MeO2, with large theoretical capacity are regarded as an important class of cathode materials for sodium-ion batteries (SIBs). However, they usually exhibit inferior thermodynamic stability and sluggish Na + kinetics due to the unwanted phase transitions and large Na + -ionic radius. In this work, considering the beneficial synergistic effects of layered P2/P3 and Fd 3̄ m spinel phases, a stable layered/spinel intergrowth nanocomposite Na0.5 [Ni0.2 Co0.15 Mn0.65 ]O2 is rationally designed and successfully prepared via a co-precipitation route and a subsequent solid-state reaction, and the triphase synergy in this layered/spinel nanocomposite is demonstrated. In Na/Na0.5 [Ni0.2 Co0.15 Mn0.65 ]O2 half-cells, it delivers a high specific capacity of ∼180 mA h g −1 and a good cycling stability, with a capacity retention of 87.6% after 100 cycles, at a rate of 0.1C between 1.5 and 4.0 V ( vs. Na/Na + ). The large reversible capacity of 105 mA h g −1 is also achieved even at a high rate of 10C, indicating high-rate capability. Besides, the full-cells using this nanocomposite as the cathode and hard carbon as the anode exhibit long-term cycle-life and high-power properties, indicating the expected merits of layered/spinel mixed phases. The superior sodium storage performance of this layered P3/P2 and spinel intergrowth nanocomposite makes it a promising candidate as a long-life and high-rate cathode for SIBs.