标题：LiNi0.5Mn1.5O4nanostructures with two-phase intergrowth as enhanced cathodes for lithium-ion batteries
作者：Zhu, Xiaobo ;Li, Xiaona ;Zhu, Yongchun ;Jin, Shasha ;Wang, Yan ;Qian, Yitai
作者机构：[Zhu, Xiaobo ;Li, Xiaona ;Zhu, Yongchun ;Jin, Shasha ;Wang, Yan ;Qian, Yitai ] Hefei National Laboratory for Physical Science at Microscale, Departmen 更多
摘要：LiNi0.5Mn1.5O4(LNMO) nanostructures (microspheres composed of nanoparticles) are prepared from urchin-like γ-MnO2by calcinating under 800 C, the product shows Fd3m-based phase involving minor rock salt phase and Mn3+ions confirmed by its Raman spectra, X-ray diffraction pattern and electrochemical activities. Furthermore, HRTEM images and EDS line-scanning spectroscopy patterns focusing on a single nanoparticle provide direct observation of intergrowth of two phases that minor P4332 phase is found on the edge of Fd3 m body coupled with the varying Mn/Ni ratio. In comparison, the other sample is obtained by adding an annealing treatment at 700 C after calcinating at 800 C, which preserves the nanostructured architecture of C800 and displays all the structural characteristics of pure P4332 phase. As cathode materials for lithium-ion batteries, merely calcined sample receives discharge capacities of 91 mAh•g-1even at 50 C, and 100.5 mAh•g-1after 300 cycles at 5 C, which shows better combination of rate and cycling performances than its counterpart with pure P4332 phase. © 2014 Elsevier Ltd.