Composite of Fe3O4/MnCO3 as anodes for lithium-ion batteries

Highlights: • A novel composite of Fe₃O₄/MnCO₃ is served as lithium-ion battery. • The composite of Fe₃O₄/MnCO₃ was prepared by one-step solvothermal method. • The composite exhibits long-term cyclability and good conductivity. • The structure of Fe₃O₄/MnCO₃ composite was formed by homogeneous spheres. A novel near in situ composite of Fe₃O₄/MnCO₃, with solid microsphere structure, is prepared by a simple one-step solvothermal method. Energy dispersive X-ray spectrometer (EDS) mappings and XRD patterns show that the multicomponent materials are composited mixing of MnCO₃ and Fe₃O₄. The cyclic voltammogram curves of the Fe₃O₄/MnCO₃ composite look like that the curves of Fe₃O₄ are superimposed on the curve of MnCO₃. It's implicated that the electrochemical process of the composite is the simple addition of Fe₃O₄ and MnCO₃ materials. The Fe₃O₄/MnCO₃ composite delivers a reversible capacity of 617 mA h g^-1 at 100 mA g⁻¹ after 100 cycles, much higher than that of pure MnCO₃ (287 mA h g^-1) and pure Fe₃O₄ (473 mA h g^-1). Compared to MnCO₃ and Fe₃O_4, the superior electrochemical performance of Fe₃O₄/MnCO₃ composite electrode can be attributed to composition with microspheres structure and good conductivity.