Na2MnPO4F材料是一种很有发展前景的钠离子电池正极材料，本文通过非原位XRD和固体核磁共振技术研究该材料充放电结构变化（晶体结构与局域Na位）. 非原位XRD测试发现，充电过程在2θ为31o和36o左右出现新的衍射峰，表明钠脱出后电极上有中间相物质生成. 23Na MAS NMR谱图的-209 ppm、-258 ppm和-295 ppm三个谱峰分别对应于该材料结构中Na1 + Na2位、Na3位和Na4位. 非原位23Na MAS NMR谱研究发现，充电过程中-209 ppm处信号峰面积比例减小，表明Na1和Na2位的Na比Na3和Na4位先脱出. 充电至4.2 V，-132 ppm和-330 ppm处出现中间相物质的信号峰；而放电过程则相反.
The Na2MnPO4F is one of the promising cathode materials for the sodium ion batteries. In the paper, we employed the ex situ X-ray diffraction and solid state NMR techniques to study the charge and discharge processes of this material, including the crystal structure and sodium sites changes. The ex situ x-ray diffraction patterns showed that two new diffraction peaks could be observed at 31o and 36o indicating an intermediate phase formed with the extraction of Na+. From the 23Na MAS NMR spectrum of the material, three peaks were seen at -209 ppm，-258 ppm and -295 ppm, which can be assigned to Na1 + Na2, Na3 and Na4 sites in the crystal structure, respectively. The ex situ solid state NMR study demonstrated that the Na+ in Na1 and Na2 sites deintercalated firstly compared to Na3 and Na4 sites. The signal peaks of intermediate phase appeared at -132 ppm and -330 ppm when charging to 4.2 V. The opposite phenomenon occurred during the discharge process.
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