Rong A, Gao X P, Li G R, Yan T Y, Zhu H Y, Qu J Q, Song D Y
Institute of New Energy Material Chemistry, Department of Materials Chemistry, Nankai University, Tianjin 300071, China.
J Phys Chem B. 2006 Aug 3;110(30):14754-60. doi: 10.1021/jp062875r.
Spinel Zn2SnO4 particles with the cubic shape are prepared via a hydrothermal reaction under mild conditions. The hydrothermal conditions, such as alkaline concentration, reaction temperature, and duration time, have an important influence on the product structure and the performance of the electrode prepared with the product. The optimized product is cube-shaped Zn2SnO4 crystalline, which is prepared with 0.4 M of NaOH solution at 200 degrees C for 24 h. These cube-shaped Zn2SnO4 particles with the spinel structure exhibit a large electrochemical capacity of 988 mA h/g and a relatively good capacity retention as anode materials for Li-ion battery. The structures of the as-prepared product and specimens taken from the electrodes after charging-discharging cycles are analyzed by X-ray diffraction, scanning electron microscopy, and transition electron microscopy techniques. In particular, it is found for the first time that the spinel Zn2SnO4 structure exists to a great extent after the first cycle and contributes to the extremely high reversible capacity during the following cycles.
通过温和条件下的水热反应制备了立方形状的尖晶石型Zn2SnO4颗粒。水热条件,如碱浓度、反应温度和持续时间,对产物结构以及用该产物制备的电极性能有重要影响。优化后的产物是立方体形的Zn2SnO4晶体,它是在200℃下用0.4 M的NaOH溶液制备24小时得到的。这些具有尖晶石结构的立方体形Zn2SnO4颗粒作为锂离子电池的负极材料表现出988 mA h/g的大电化学容量和相对良好的容量保持率。通过X射线衍射、扫描电子显微镜和透射电子显微镜技术对所制备产物以及充放电循环后从电极上取下的样品的结构进行了分析。特别地,首次发现尖晶石Zn2SnO4结构在第一次循环后很大程度上仍然存在,并对随后循环中的极高可逆容量有贡献。