VOPO4·2H2O, as a new cathode material for Ca-ion batteries, exhibits a discharge capacity of 100.6 mA h g-1, excellent cycling stability (200 cycles) and good rate performance (42.7 mA h g-1 at 200 mA g-1). In situ X-ray diffraction and in situ Raman results demonstrate the calcium-ion-storage mechanism of VOPO4·2H2O is a single-phase reaction based on asymmetric Ca2+ insertion and deinsertion.

中文翻译：

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VOPO4·2H2O作为可再充电钙离子电池的新型正极材料。

VOPO4·2H2O作为Ca离子电池的新型阴极材料，具有100.6 mA h g-1的放电容量，出色的循环稳定性（200个循环）和良好的倍率性能（在200 mA g-下为42.7 mA h g-1） 1）。原位X射线衍射和原位拉曼光谱结果表明VOPO4·2H2O的钙离子存储机理是基于不对称Ca2 +插入和去插入的单相反应。