三维SnO2/C/rGO复合纤维膜电极制备及储锂性能
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摘要：
三维(3D)纳米纤维复合膜电极结构设计,避免了电极片制备过程中导电剂、黏结剂的添加,增强了电解液的浸润能力,对改善锂离子电池容量及倍率性能具有重要的价值和意义.采用同步静电纺丝和静电喷雾技术,结合氩气煅烧技术,制备了3D网络结构SnO2/C/rGO复合纤维薄膜电极.这种由一维(1D)SnO2/C纳米线组合二维(2D)石墨片构成3D纳米复合纤维薄膜电极,一方面通过碳纤维连续包覆SnO2颗粒,有利于缓解SnO2充放电过程中剧烈的体积变化,增强其稳定性;另一方面通过碳纤维与二维石墨烯复合构成3D网络结构,有利于改善纤维膜电极的导电性,进而提高其倍率性能.研究表明,制备的SnO2/C/rGO复合纤维膜电极展示了其优良的放电容量、倍率性能及循环稳定性.于电流密度为0.4、0.8、1.6、2.4和4A·g^-1时,10次循环后放电容量分别达到797、659、626、534和468mAh·g^-1,且当电流密度回落至0.4A·g^-1时放电容量可恢复到709mAh·g^-1;4A·g^-1充放电540次电极容量仍可达457mAh·g^-1,库伦效率接近100%.
The structure of three-dimensional (3D) nanofiber composite film electrode avoids the addition of conductive agent and binder in the preparation of electrode, and it has huge value and significance for improving the capacity and rate capability performance of lithium ion battery. SnO 2/C/rGO composite nanofiber films with 3D grid structure were synthesized through synchronous electrospun and electrospry technology combined with argon calcination technology. On the one hand, continuous SnO 2 nanoparticles coated with carbon fiber can alleviate the drastic volume change during charging and discharging of SnO 2 and keep the stability of electrode. On the other hand, one-dimensional carbon fiber and two-dimensional graphene are combined to form a 3D network structure, which is improved the conductivity of the fiber film electrode. The results show that as-prepared SnO 2/C/rGO composite fiber film electrode can deliver the discharge a capacity of 797, 659, 626, 534 and 468 mAh·g^-1 at the current density of 0.4, 0.8, 1.6, 2.4 A·g^-1 and 4 A·g^-1 for 10 cycles. When the current density went back to 0.4 A·g^-1 , its capacity could restore 709 mAh·g^-1 . Besides, the composite electrode can still release a high discharge capacity of 457 mAh·g^-1 at the current density of 4 A·g^-1 after 540 cycles (almost 100% coulombic efficiency), which shows an excellent electrochemistry performance.
作者：
杨震宇 魏海燕
Yang Zhenyu;Wei Haiyan(College of Chemistry, Nanchang University, Nanchang 330031,China)
机构地区：
南昌大学化学学院
出处：
《betway官方app 学报：自然科学版》 CAS 北大核心 2019年第4期56-63,F0002,共9页
基金：
国家自然科学基金(21863006 21263016) 江西省重点研发项目(2012BBE50022)
关键词：
同步静电纺丝和静电喷雾技术 SnO2/C/rGO 纳米纤维复合膜 电极
synchronous electrospun and electrospray SnO 2/C/rGO nanofiber composite film elecrode
分类号：
O646 [理学—物理化学]
