In this paper, MoO3 hollow microspheres were synthesized via a facile and template-free solvothermal route and subsequent heat treatment in air. The MoO3 hollow microspheres have a relatively high specific surface area, and with such a feature, the as-synthesized MoO3 hollow microspheres have potential applications in Li-ion battery and gas-sensor. When tested as a Li-storage anode material, the MoO3 hollow microspheres show a higher discharge capacity of 1377.1 mA h g(-1) in the first discharge and a high reversible capacity of 780 mA h g(-1) after 100 cycles at a rate of 1 C. Furthermore, as a gas sensing material, the MoO3 hollow microspheres exhibit an improved sensitivity and short response/recovery time to trace levels of ammonia gas. (C) 2013 Elsevier Ltd. All rights reserved.