MoO2/C nanocomposite has been prepared by simultaneously reducing as-prepared MoO3 nanosheets and introducing an amorphous carbon matrix in the combination of facile hydrothermal and post annealing processes. MoO2 nanoparticles are uniformly embedded in the carbon framework, resulting in porous nanostructured MoO2/C composite material. The MoO2/C electrodes exhibit varied electrochemical working mechanisms for sodium ion storage that is dependent on charge/discharge rates. At low charge/discharge rate conditions, MoO2/C nanocomposite shows dominant battery performances for sodium ion storage involving reversible conversion reaction of MoO2. The MoO2/C anode material can deliver high initial charge capacity of 557.2 mAh/g at 0.1C (1C= 600 mA/g), along with good cycling stability in comparison with bare MoO2 material. At high rate situations, cyclic voltammetric (CV) results indicate distinct pseudocapacitive behaviors of MoO2/C materials when the scanning rate is higher than 0.5 mV/s. Specific capacitances of 123.25, 85.47 and 49.90 Fig can be obtained from CV measurements conducted at 1, 2 and 5 mV/s, respectively. These electrochemical performances illustrate remarkable capabilities of MoO2/C nanocomposite as anode material for sodium ion storage involving varied conversion reactions and pseudocapacitive sodiation/desodiation reactions depending on charge/discharge rates. (C) 2017 Elsevier Ltd. All rights reserved.