纳米花状MoO_(3−x)负极的制备及电化学性能

Preparation and electrochemical properties of nanoflower MoO_(3−x)anodes

三氧化钼(MoO_(3))由于自身理论比容量高、热稳定性好以及二维层状结构,成为目前广受关注的锂离子电池负极材料之一。但是,由于MoO_(3)自身的本征导电率低以及转换反应过程中严重的体积膨胀,限制了MoO_(3)的大规模应用。本文通过质子−电子共掺杂以及高能纳米化方式,在MoO_(3)中引入了氧空位和纳米花结构,制备了纳米花MoO_(3−x)材料,并将其用作锂离子电池负极。通过引入氧空位以及进行纳米化处理,有效改善了材料的导电性能,扩大了范德华间隙,缓冲了材料在长期充放电过程中的体积膨胀。结果表明,所制备的纳米花MoO_(3−x)具有良好的锂离子存储性能,在2 A/g的电流密度下能够循环500圈,比容量能够达到591 mA∙h/g,显著高于以往报道的三氧化钼基负极材料。

Molybdenum trioxide(MoO_(3))has become one of the most popular anode materials for lithium-ion batteries due to its high theoretical specific capacity,good thermal stability and two-dimensional layered structure.However,the low intrinsic conductivity of MoO_(3)and the rapid capacity decay limit the large-scale application of MoO_(3)during cycling.In this paper,oxygen vacancies and nanoflower structures were introduced into MoO_(3)by proton-electron co-doping and high-energy nanosizing,and N-MoO_(3−x)materials were prepared and used as anode for lithium-ion batteries.By introducing oxygen vacancies and nanosizing,the conductivity of the material is effectively improved,the van der Waals gap is expanded and the volume expansion of the material is buffered during long-term charge and discharge.The results show the prepared nanoflower MoO_(3−x)has good lithium storage performance.It can cycle 500 cycles at current density of 2 A/g and the specific capacity can reach 600 mA∙h/g.The N-MoO_(3−x)materials is significantly higher than the previously reported molybdenum trioxide-based anode materials.