水热法合成氧化铁/石墨烯复合材料及其电化学性能研究

Synthesis of Fe_2O_3/GO Composite by Hydrothermal Method and Its Electrochemical Performances

通过一步水热法合成了Fe_2O_3/GO复合材料,得到的氧化铁能很好地与石墨烯复合在一起,并且具有比同方法得到的纯Fe_2O_3更小的颗粒直径.Fe_2O_3/GO复合材料表现出了很好的电化学性能,在1.0 A·g^(-1)的电流密度下能够释放出高达726/715 mAh·g^(-1)的放/充容量,其循环稳定性也得到大大提高.石墨烯的有效复合不仅为电极材料提供了高的导电性,而且有效缓解反复充放电过程中体积效应带来的应力集中,防止材料粉化脱落,从微观结构的改进中有效提升了材料的宏观电化学性能.

Fe2O3/GO composite is synthesized through a one-pot hydrothermal method.The as-prepared Fe2O3 is well composited with graphene.It reveals a smaller particle size than that of the pure Fe2O3 obtained in the same way.Enhanced electrochemical performances are obtained for Fe2O3/GO.The electrode can deliver discharge/charge capacities of 726/715 mAh·g-1 at the current density of 1.0 A·g-1.Furthermore,the cycle stability of the electrode is also significantly improved.It proves that graphene in the composite not only offers a high conductivity of electron,but also releases the stress brought from the volumetric effect during repeated charge-discharge processes.Thus,it stops that pulverization of the electrode and improves the electrochemical properties through the regulation of the microstructures.