Thamodaran Partheeban, Murugan Vivekanantha, Sundaramurthy Devikala, Sekar Karthikeyan, Maruthapillai Arthanareeswari, Maruthapillai Tamilselvi
Department of Chemistry, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India.
Department of Physics and Nanotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India.
ACS Omega. 2022 Jul 22;7(30):26523-26530. doi: 10.1021/acsomega.2c02558. eCollection 2022 Aug 2.
Sodium superionic conductor (NASICON)-structured NaV(PO)F cathode materials have received vast attention in the high-temperature storage performance due to their structural and thermal stability. Herein, hierarchical NaV(PO)F microspheres (NVPF-HMSs) consisting of nanocubes were designed by a one-pot facial solvothermal method. The hierarchical NaV(PO)F microsphere size is 2-3 μm, which is corroborated by FE-SEM and HR-TEM analyses. The NVPF-HMSs have been demonstrated as a cathode in Li-ion batteries at both low and elevated temperatures (25 and 55 °C, respectively). The NVPF-HMS cathode in a Li-ion cell exhibits reversible capacities of 119 mA h g at 0.1 C and 85 mA h g at 1 C with an 82% retention after 250 cycles at 25 °C. At elevated temperatures, the NVPF-HMS cathode exhibits a superior capacity of 110 mA h g at 1 C along with a retention of 90% after 150 cycles at 55 °C. Excellent capacity and cyclability were achieved at 55 °C due to its hierarchical morphology with a robust crystal structure, low charge-transfer resistance, and improved ionic diffusivity. The Li-ion storage performance of the NVPF-HMS cathode material at elevated temperatures was analyzed for the first time to understand the high-temperature storage property of the material, and it was found to be a promising candidate for elevated-temperature energy storage applications.
钠超离子导体（NASICON）结构的NaV(PO)F正极材料因其结构和热稳定性，在高温存储性能方面受到了广泛关注。在此，通过一锅法简易溶剂热法设计了由纳米立方体组成的分级NaV(PO)F微球（NVPF-HMSs）。分级NaV(PO)F微球尺寸为2-3μm，这通过场发射扫描电子显微镜（FE-SEM）和高分辨率透射电子显微镜（HR-TEM）分析得到证实。NVPF-HMSs已被证明可作为锂离子电池在低温和高温（分别为25℃和55℃）下的正极。锂离子电池中的NVPF-HMS正极在25℃下，0.1C时可逆容量为119 mA h g，1C时为85 mA h g，在250次循环后保持率为82%。在高温下，NVPF-HMS正极在55℃下1C时表现出110 mA h g的优异容量，在150次循环后保持率为90%。由于其具有坚固晶体结构的分级形态、低电荷转移电阻和改善的离子扩散率，在55℃下实现了优异的容量和循环性能。首次分析了NVPF-HMS正极材料在高温下的锂离子存储性能，以了解该材料的高温存储特性，结果发现它是高温储能应用的一个有前途的候选材料。
