钠离子电池正极材料Na3V2(PO4)2O2F的控制合成与电化学性能优化  

Controlled Preparation and Performance Optimization of Na_3V_2(PO_4)_2O_2F as Cathode Material for Sodium Ion Batteries

作　　者：谷振一 郭晋芝 杨洋 吕红艳 赵欣欣 席晓彤 何晓燕[1] 吴兴隆 GU Zhen-Yi;GUO Jin-Zhi;YANG Yang;Lv Hong-Yan;ZHAO Xin-Xin;XI Xiao-Tong;HE Xiao-Yan;WU Xing-Long(College of Chemistry and Environmental Science,Yili Normal University,Yining,Xinjiang 835000,China;National&Local United Engineering Laboratory for Power Batteries,Faculty of Chemistry,Northeast Normal University,Changchun 130024,China)

机构地区：[1]伊犁师范学院化学与环境科学学院,伊犁835100 [2]东北师范大学化学学院,动力电池国家地方联合工程实验室,长春130024

出　　处：《无机化学学报》2018年第9期1641-1648,共8页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.51602048)和中央高校基本科研业务费专项资金(No.2412017FZ013)资助项目。

摘　　要：采用简单的水热合成法制备氟磷酸钒氧钠(Na_3V_2(PO_4)_2O_2F,简写为NVPOF),通过调节水热反应溶液的pH值和反应温度等关键参数,有效调节NVPOF的颗粒尺寸和均匀性,优化其电化学性能。研究结果显示,性能最优的NVPOF的合成条件是:pH值为7.00±0.05,水热反应温度为170℃。在该条件下合成的NVPOF正极材料具有优异的电化学性能,表现为0.1C(1C=130 mA·g^(-1))的倍率下放电比容量可达123.2 mAh·g^(-1),且在20C的高倍率下仍可实现85.9 mAh·g^(-1)的比容量,在1C下循环200圈后其容量保持率为96.2%,表明该材料具有高容量、优异的倍率和循环性能。所制备的NVPOF颗粒为纳米尺度且具有很高的均匀性,可缩短Na^+的传输路径从而缩短其传输时间,且NVPOF晶体结构具有高稳定性,是一类具有高性能的钠离子电池正极材料。A simple hydrothermal preparation method was developed to prepare sodium fluoride phosphate vanadium oxide(Na3V2(PO4)2O2F,abbreviated as NVPOF)material,regulating the morphology and size of the NVPOF by adjusting the key parameters including the pH value and hydrothermal temperature.The optimized NVPOF material exhibits the highest particle-size uniformity and thereby the best electrochemical properties.The pH value is 7.00±0.05 and the hydrothermal temperature is 170℃,which is the optimized parameters for the NVPOF preparation.The NVPOF material prepared at this condition delivers the specific capacity of 123.2 mAh·g^-1 at 0.1C(1C=130 mAh·g^-1)and 85.9 mAh·g^-1 at a high rate of 20C.The capacity retention is 96.2%after 200 cycles at 1C.All of the results indicate its high capacity,excellent rate and long cycle stability for Na storage.This is mainly attributed to the nanometer size and high uniformity of the NVPOF particles,which can provide the short Na+transport path and hence shorten the time.Combining with the high stability of crystal structure,the optimized NVPOF material exhibits excellent performance as practical cathode for SIBs.

关 键 词：钠离子电池正极材料的优化 高性能正极材料 水热合成 Na3V2(PO4)2O2F 钠离子扩散动力学 

分 类 号：O646[理学—物理化学]