Time-efficient synthesis of MnO2 encapsulated α-Fe2O3 ellipsoids for lithium ion battery applications

Herein, Fe2O3 was enlisted as an environmentally benign and inexpensive anode active material. A facile time-efficient synthesis strategy was developed to prepare hematite Fe2O3 ellipsoid particles via hydrothermal method. The structural and morphological properties of the prepared materials were characterized using XRD, FE-SEM, HR-Raman, and HR-TEM. The electrochemical properties were investigated using galvanostatic cycling, cyclic voltammetry, and impedance spectrum analysis. To further overcome the drawbacks of alpha-Fe2O3 ellipsoids, a MnO2 coating was applied. The encapsulated alpha-Fe2O3 ellipsoids exhibited improved electrochemical properties, such as a high specific capacity, high coulombic efficiency, stable cyclic performance, and a high rate capability. The improved electrochemical performance of the ellipsoids could be attributed to the uniform and continuous MnO2 layer coatings, yielding an enormous advantage through the sustained integrity of nanoparticles, stimulating the electronic conductivity of electrode materials leading to the formation of a thin SEI (Solid Electrolyte Interphase) layer on the electrode surface, and by maintaining the as-formed layer. The obtained results demonstrated MnO2 encapsulated alpha-Fe2O3 ellipsoid particles as a superior anode material for lithium ion batteries compared to bare alpha-Fe2O3 and commercially available graphite electrodes. (C) 2017 Elsevier B.V. All rights reserved.