Fe掺杂宣纸基碳纤维材料的储锂性能

Lithium storage performance of Fe-doped Xuan paper-based carbon fiber materials

为了改善目前锂离子电池电极材料的成本高、环境污染等问题,本文提出了一种由植物纤维构成的宣纸直接烧结炭化并对其进行改性之后作为锂离子电池负极材料的方法。通过改变烧结温度和时间,探究宣纸的最佳炭化机制,之后通过简单的溶液法和烧结法掺杂入Fe对宣纸基碳纤维材料进行改性。并通过X射线衍射光谱(XRD)、扫描电镜(SEM)和X射线能谱分析(EDS)等分析手段对制备的材料进行了表征和对比,结果表明Fe成功均匀掺入到宣纸的原材料中。材料有很强的柔性可直接作为电极使用,结构均匀且稳定,并且在微观结构上,表面较之前呈现出了很多均匀的微孔。通过恒流充放电法分析了所制备宣纸材料作为锂离子电池负极的储锂性能。结果表明,在500mA/g电流密度下锂离子电池容量首圈可达到565.4mA·h/g,当电流密度高达2500mA/g时可逆容量仍然能够保持在124.7mA·h/g;在1000mA/g电流密度下可以保持稳定的长循环至1000圈。

In order to improve the high cost and environmental pollution of current lithium-ion battery electrode materials,a method of directly sintering and carbonizing Xuan paper made of plant fibers and modification of it as a lithium-ion battery anode electrode material was proposed.By changing the sintering temperature and time,the optimal carbonization mechanism of Xuan paper was explored,and then the Xuan paper-based carbon fiber materials were modified by doping Fe in a simple solution method and sintering method.The prepared materials were characterized and compared by X-ray diffraction spectroscopy(XRD),scanning electron microscopy(SEM)and X-ray energy spectroscopy(EDS).The results showed that Fe was successfully incorporated into the raw materials of Xuan paper.The material had strong flexibility and can be used directly as an electrode.The structure was uniform and stable,and the upper surface of the microstructure had many uniform micropores than before.The lithium storage performance of the prepared Xuan paper material as the anode electrode of the lithium ion battery was analyzed by the constant current charge and discharge method.The results showed that the first cycle specific capacity of the lithium-ion battery can reach 565.4mA·h/g at a current density of 500mA/g,and can still maintain a high capacity of 124.7mA·h/g when current density up to 2500mA/g.Besides,a stable and long lifespan of 1000 cycles at a current density of 1000mA/g can be also obtained.