Porous ternary TiO2/MnTiO3@C hybrid microspheres as anode materials with enhanced electrochemical performances

Porous TiO2/Mn3O4 nanocomposite microspheres have been successfully fabricated through impregnating Mn2+ ions into the lab-made porous TiO2, followed by an annealing process. The carbon-coated TiO2 and MnTiO3 (TiO2/MnTiO3@C) ternary hybrid composites with a specific surface area of 40.0 m(2) g(-1) were obtained by carbonizing the pyrrole coated porous TiO2/Mn3O4 microspheres. The carbon coating with a thickness of 1-2 nm was deposited on the surface and inner wall of pores. Electrochemical tests demonstrated that the as-prepared TiO2/MnTiO3@C porous electrode materials possessed a reversible capacity of 402.6 mA h g(-1) after 300 cycles at a current density of 100 mA g(-1) and the capacities of 259.8, 237.3, 200.4, 150.5 and 103.3 mA h g(-1) at the current densities of 100, 200, 400, 800, and 1600 mA g(-1). The MnTiO3/TiO2@C porous composites exhibited superior cycling and rate performances, arising from the synergistic effect that was created by little volume variation of the TiO2 matrix, high capacity of MnTiO3 and good electrical conductivity of the carbon coating during the charge/discharge processes.