C@MnO_(2)复合纳米纤维阴极的制备及在Zn^(2+)电池中的应用  

Preparation of C@MnO_(2)composite nanofiber cathode and its application in Zn^(2+)batteries

作　　者：方雪松 熊杰[2] 宋立新[2] FANG Xuesong;XIONG Jie;SONG Lixin(School of Materials Science&Engineering,Zhejiang Sci-Tech University,Hangzhou 310018,China;College of Textile Science and Engineering(International Institute of Silk),Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]浙江理工大学材料科学与工程学院,杭州310018 [2]浙江理工大学纺织科学与工程学院(国际丝绸学院),杭州310018

出　　处：《现代纺织技术》2023年第5期41-48,共8页Advanced Textile Technology

基　　金：浙江理工大学研究生培养基金项目(2021)。

摘　　要：为解决MnO_(2)在锌离子电池充放电中导电性差的问题,将MnO_(2)与碳纳米纤维复合以提高MnO_(2)的导电性,通过微观核壳结构的设计改善MnO_(2)充放电过程中的溶解问题。以静电纺丝和退火相结合的方法成功制备了碳纳米纤维,采用湿化学方法和水热法使KMnO 4在碳纳米纤维的表面还原为MnO_(2)。XRD证实了α-MnO_(2)和β-MnO_(2)的存在且无杂质产生,SEM照片显示成功制备了核壳结构的C@MnO_(2)复合纳米纤维。电化学测试结果表明在0.1 A g恒流充放电下,循环100次仍有83%的容量保持率,且可提供163.89 mAh g的可观比容量。该长循环性能得益于碳纳米纤维与MnO_(2)的协同作用,导电性的碳纳米纤维作为骨架促进了电子转移动力学,而MnO_(2)纳米片提高了活性材料与电解液的接触面积,促进了Zn^(2+)扩散。此外,MnO_(2)与碳纳米纤维紧密连接在一起,形成了完整均一的结构也最大程度地改善了MnO_(2)在充放电过程中的体积变化与溶解问题。The growing environmental concerns and energy consumption are driving an ever-increasing pursuit for advanced energy storage system with high energy density,environmental friendliness,and high safety.Although lithium-ion batteries(LIBs)dominate the battery market due to their light weight,high energy density,and long cycle life,the application of LIBs as large-scale energy storage systems has been plagued by the safety issues and environmental problems associated with flammable organic electrolytes.In recent years,aqueous rechargeable batteries,which feature high safety,eco-friendliness,and high ion conductivity of water-based electrolyte have been considered as promising alternatives to overcome these dilemmas.Rechargeable zinc-ion batteries(ZIBs)are in the spotlight of grid-scale electrical energy storage owing to the advantages of aqueous electrolyte and Zn metal anode.Manganese-based materials are often used as cathode materials for zinc ion batteries(ZIBs),which have the advantages of high theoretical capacity,low cost,low toxicity and various valence states.However,inherent poor conductivity,sluggish zinc ion diffusion kinetics and terrible rate performance limit their practical application.MnO_(2)was combined with carbon nanofibers to improve its electrical conductivity.The dissolution of MnO_(2)in charge and discharge process is alleviated by designing the microcore-shell structure.Carbon nanofibers were successfully prepared by electrospinning and annealing,and then KMnO 4 was reduced to MnO_(2)on the surface of carbon nanofibers by wet chemical method.At the current density of 0.1 A g,the prepared C@MnO_(2)still has a capacity retention rate of 83%after 100 cycles,and can provide respectable specific capacity of 163.89 mAh g.The excellent long cycle performance of this material is attributed to the synergistic action of carbon nanofibers and MnO_(2).The conductive carbon nanofibers act as the skeleton to promote the electron transfer kinetics,while the MnO_(2)nanosheets improve the contact area between

关 键 词：二氧化锰 碳纳米纤维 锌离子电池 水热法 阴极 

分 类 号：TB383.1[一般工业技术—材料科学与工程]