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采用喷雾干燥制备前驱体,经高温烧结制得有电化学活性的钠离子电池NaMnPO4正极材料.X射线衍射(XRD)分析证明,合成的NaMnPO4材料为正交晶系、Pmnb空间群的磷钠锰矿(Natrophilite)型材料.扫描电镜(SEM)及透射电镜(TEM)结果显示,喷雾干燥得到的前驱体为空心球粒子,经高温烧结后,该材料由粒径几十纳米的NaMnPO4纳米晶一次颗粒及无定形碳网络结构相互连接组成的微米级二次颗粒构成.电化学测试表明,NaMnPO4/C复合结构显著改善了材料的离子电导与电子电导,首次报道电流密度为7.75 m A·g-1、电压范围为1.0~4.5 V(vs.Na+/Na)时,钠离子电池NaMnPO4正极材料的可逆放电比容量达90 m Ah·g-1.
The precursor of NaMnPO4 was electrochemically activated by high temperature sintering using spray drying, and the XRD analysis showed that the synthesized NaMnPO4 material was orthorhombic and Pmnb space group (Natrophilite) .SEM and TEM results showed that the precursors obtained by spray drying were hollow spherical particles. After sintering at high temperature, the material consisted of NaMnPO4 nanocrystalline primary particles with particle size of several tens of nanometers And amorphous carbon network structure. The electrochemical tests showed that NaMnPO4 / C composite structure significantly improved the ionic conductivity and electronic conductivity of the material, the first reported current density of 7.75 m A · g-1 , The reversible discharge capacity of NaMnPO4 cathode material for sodium ion battery reaches 90 m Ah · g-1 at the voltage range of 1.0-4.5 V (vs. Na + / Na).