Fabrication and electrochemical investigation of MWO4 (M = Co, Ni) nanoparticles as high-performance anode materials for lithium-ion batteries

In this work, the MWO4 (M = Co, Ni) nanoparticles were successfully synthesized by a facile one-step hydrothermal method and used as novel anode materials for LIBs. The micromorphology of obtained CoWO4 and NiWO4 was uniform nanoparticles with the size of similar to 60 and similar to 40 nm, respectively, by structural characterization including X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). When tested as lithium-ion battery anode, CoWO4 nanoparticles exhibited a stabilized reversible capacity of 980 mA h g(-1) at 200 mA g(-1) after 120 cycles and 632 mA h g(-1) at 1000 mA g(-1) even after 400 cycles. And, the discharge capacity was as high as 550 mA h g(-1) at the 400 th cycle for NiWO4 nanoparticles. The excellent electrochemical performance could be attributed to the unique nanoparticles structure of the materials, which can not only shorten the diffusion length for electrons and lithium ions but also provide a large specific surface area for lithium storage.