Synthesis of porous MoV2O8 nanosheets as anode material for superior lithium storage

Vanadium-based mixed oxides are promising for high-energy-density lithium-ion batteries (LIBs) due to their abundant oxidation states, complex chemical compositions and synergistic effects, but the large volume change upon lithiation/delithiation limits the electrochemical properties. Two-dimensional nanostructures have great potential in the development of electrode materials by promoting the ion transport and alleviating the volume change. Herein, porous MoV2O8 nanosheets are synthesized via a solvothermal process followed by thermal treatment without using any surfactants. Benefiting from the nanosheet structure with large surface area and abundant pores, the MoV2O8 electrode exhibits impressive lithium storage properties with superior rate performance and prolonged cyclability. Superior reversible capacities of 1396 and 570 mA h g(-1) can be maintained after 120 cycles at 200 mA g(-1) and after 1000 cycles at 10 A g(-1), respectively. Furthermore, the lithium storage mechanism of the MoV2O8 nanosheets was investigated by in-situ X-ray diffraction, ex-situ X-ray diffraction and X-ray photoelectron spectroscopy measurements, which confirms the synergistic effects of Mo and V upon lithiation/delithiation. In addition, a full cell consisting of the MoV2O8 nanosheets and commercial LiFePO4 exhibited good electrochemical performance, demonstrating the great potential of the MoV2O8 nanosheets as an anode material for LIBs.