MoO2–ordered mesoporous carbon hybrids as anode materials with highly improved rate capability and reversible capacity for lithium-ion battery

Abstract

A novel hybrid of MoO₂–ordered mesoporous carbon (MoO₂–OMC) was prepared through a two-step solvothermal chemical reaction route. The electrochemical performances of the mesoporous MoO₂–OMC hybrids were examined using galvanostatical charge–discharge, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS) techniques. The MoO₂–OMC hybrid exhibits significantly improved electrochemical performance of high reversible capacity, high-rate capability, and excellent cycling performance as an anode electrode material for Li ion batteries. It is revealed that the MoO₂–OMC hybrid could deliver the first discharge capacity of 1641.8 mA h g⁻¹ with an initial Coulombic efficiency of 63.6%, and a reversible capacity as high as 1049.1 mA h g⁻¹ even after 50 cycles at a current density of 100 mA g⁻¹, much higher than the theoretical capacity of MoO₂ (838 mA h g⁻¹) and OMC materials. The MoO₂–OMC hybrid demonstrates an excellent high rate capability with capacity of ∼600 mA h g⁻¹ even at a charge current density of 1600 mA g⁻¹ after 50 cycles, which is approximately 11.1 times higher than that of the OMC (54 mA h g⁻¹) materials. The improved rate capability and reversible capacity of the MoO₂–OMC hybrid are attributed to a synergistic reaction between the MoO₂ nanoparticles and mesoporous OMC matrices. It is noted that the electrochemical performance of the MoO₂–OMC hybrid is evidently much better than the previous MoO₂-based hybrids.