【摘要】 采用简单水热法和后续高温煅烧制备多孔结构V₂O₅微球,用X射线衍射仪分析V₂O₅微球的晶体结构,通过扫描电镜和透射电镜观察和分析微球表面形貌与微观结构。结果表明,微球为单相V₂O₅,呈形貌均一的多孔结构。作为锂离子电池正极材料,V₂O₅多孔微球电极在不同电压区间均显示出优异的电化学性能,在2.5～4.0 V电压范围内,100 mA/g的电流密度下,初始放电比容量达到145 （mA·h）/g,接近理论值147 （mA·h）/g,循环50圈后仍保持在138 （mA·h）/g,容量保持率高达95.2%。此外,该电极还表现出优异的长循环稳定性,在2 A/g的电流密度下循环1 000圈后放电比容量保持在82.8 （mA·h）/g,平均单圈比容量衰减率仅为0.022%。该材料优良的电化学性能得益于三维多孔微球结构。更多还原

【Abstract】 Porous V₂O₅ microspheres were synthesized by a facile hydrothermal reaction followed by high temperature calcination.The crystal structure of V₂O₅ microspheres was analyzed by X-ray diffraction（XRD）.The morphology and microstructure were observed and analyzed by scanning electron microscopy（SEM） and transmission electron microscopy（TEM）.The results show that the microspheres are single phase V₂O₅ with homogeneous porous morphology.As cathode material for lithium batteries,porous V₂O₅ microspheres electrode exhibits excellent electrochemical performance at different voltage ranges.The initial discharge capacity of the porous V₂O₅ microspheres electrode is145（mA·h）/g at the current density of 100 m A/g during 2.5-4 V,which is very close to the theoretical value.The capacity retention is 95.2% based on the initial capacity after 50 cycles.In addition,the electrode demonstrates excellent long-term cycling stability with the discharge specific capacity maintained at 82.8（mA·h）/g after 1 000 cycles at 2 A/g current density,and the average single-cycle specific capacity attenuation rate is only 0.022%.The excellent electrochemical properties of the material benefit from the three-dimensional porous microsphere structure.更多还原