【摘要】 以偏钒酸铵为V源，酞酸四丁酯为Ti源，通过水热反应和350℃焙烧制备微米级花球网络状V₂O₅@TiO₂复合材料。以V₂O₅@TiO₂复合材料作为锂离子电池负极材料，对其电化学性能进行了测试。结果表明，在恒流充放电电流密度为100 mA/g的条件下，循环300圈后，微粒级V₂O₅放电比容量为270 mA·h/g,同时容量保持率仅为50.2%;而在相同的测试条件下，V₂O₅@TiO₂复合材料放电比容量高达619.9 mA·h/g,容量保持率高达160.7%。V₂O₅@TiO₂复合材料能在长期循环过程中保持较高的放电比容量，主要归因于包覆的TiO₂起到了保护层的作用，抑制了V₂O₅在电解液中的溶解，且降低了Li⁺嵌入/脱出的应力，减缓了V₂O₅结构的退化。本研究结果为V₂O₅作为锂离子电池负极材料的制备和表面改性提供了一种简单有效的方法。更多还原

【Abstract】 Using ammonium metavanadate as V raw material and tetrabutyl phthalate as Ti raw material, micron-sized flower ball V₂O₅@TiO₂ composites in network shape were prepared by hydrothermal reaction and calcination at 350 ℃.The electrochemical performance of V₂O₅ @TiO₂ composites as anode materials for lithium-ion batteries was tested.The results show that under the condition of constant current charge-discharge current density of 100 mA/g, the specific discharge capacity of particulate V₂O₅ is 270 mA·h/g with a capacity retention rate of 50.2% after 300 cycles, while the specific discharge capacity of V₂O₅ @TiO₂ composites is as high as 619.9 mA·h/g with the capacity retention rate of 160.7% under the same test conditions.The ability of V₂O₅@TiO₂ composites to maintain a high specific discharge capacity during long-term cycling is mainly attributed to the coating of TiO₂ that acts as a protective layer, which inhibits the dissolution of V₂O₅ in the electrolyte and reduces the stress of Li⁺ insertion/extraction, slowing down the degradation of the V₂O₅ structure.The results of this study provide a simple and effective method for the preparation and surface modification of V₂O₅ as anode materials for lithium-ion batteries.更多还原