摘要
Fe_(3)O_(4)作为锂离子电池负极材料,在充放电时体积变化较大,导致其容量衰减严重。目前,碳包覆是解决这个问题的主要方式之一。本工作以氧化石墨烯(GO)和Fe^(2+)为原料,用一步水热法合成了三维石墨烯片包覆Fe_(3)O_(4)纳米颗粒3DG@Fe_(3)O_(4)复合材料。使用傅里叶红外光谱(FT-IR)仪、热重分析(TGA)仪、X射线衍射(XRD)仪、拉曼光谱(Raman)仪、扫描电子显微镜(SEM)对复合物进行表征,研究结果表明,复合材料呈现石墨烯(G)片包覆Fe_(3)O_(4)纳米颗粒的三明治结构。同时采用了恒流充放电(GCPL)、循环伏安(CV)以及交流阻抗(EIS)等电化学测试方法,着重研究了Fe_(3)O_(4)含量对其电化学性能的影响,Fe_(3)O_(4)质量分数为83.2%的3DG@Fe_(3)O_(4)-2电极具有最高的比容量和循环性能,在0.1 A/g的电流密度下的首次放电比容量为1412.33 mAh/g,循环100次后的放电比容量为577 mAh/g,是纯Fe_(3)O_(4)电极材料经历100次循环后的6.5倍。一步水热合成方法具有操作简单、合成条件温和及无需额外添加还原剂等优点;制备的复合电极相比纯Fe_(3)O_(4)具有电极容量高、循环稳定性能好的优势,有助于推动Fe_(3)O_(4)基负极材料在电化学领域中的应用。
As a lithium-ion battery anode material,the Fe_(3)O_(4) exhibits varying volume during charging and discharging,which results in serious capacity degradation.This problem can be solved using carbon coating.Thus,in this paper,three-dimensional graphene-coated Fe_(3)O_(4) nanoparticle(3DG@Fe_(3)O_(4)) composites were synthesized by one-step hydrothermal method using graphene oxide(GO)and Fe^(2+) as raw materials.The composites were characterized by a Fourier transform infrared spectrometer,thermal gravimetric analyzer,X-ray diffractometer,Raman spectrometer and scanning electron microscopy.The results showed that the composites have a"sandwich"structure of graphene(G)-coated Fe_(3)O_(4) nanoparticles.Meanwhile,electrochemical tests,including galvanostatic cycling with potential limitation,cyclic voltammetry,and alternating current impedance were used to investigate the influence of Fe_(3)O_(4) content on the lithium-ion storage performance of 3DG@Fe_(3)O_(4) composites.The 3DG@Fe_(3)O_(4)-2 electrode with about 83.2%Fe_(3)O_(4) exhibited enhanced specific capacity and better cycle stability.It also delivered a high discharge specific capacity of 1412.33 mAh/g at a current density of 0.1 A/g and 577 mAh/g after 100 cycles,and this value was 6.5 times that of pure Fe_(3)O_(4) electrode material after 100 cycles.The composites prepared by this method have simple synthesis and do not require additional reducing agent.The prepared composites have high capacity and good cycle stability compared with pure Fe_(3)O_(4) nanoparticles,and this can promote the application of Fe_(3)O_(4)-based anode materials in the field of energy storage.
作者
成雪莉
张维福
罗城城
袁小亚
CHENG Xueli;ZHANG Weifu;LUO Chengcheng;YUAN Xiaoya(School of materials Science and Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Chongqing Nuojiang 2D Materials Research Institute,Chongqing 400711,China)
出处
《储能科学与技术》
CAS
CSCD
北大核心
2023年第4期1066-1074,共9页
Energy Storage Science and Technology
基金
国家自然科学基金(51402030)
重庆市基础科学与前沿技术研究专项基金(cstc2017jcyjBX0028)。
