Polyoxometalate@MOF derived porous carbon-supported MoO2/MoS2 octahedra boosting high-rate lithium storage

Structural stability and rapid charge-discharge capability of electrode materials are required for high performance lithium-ion batteries (LIBs). The materials derived from polyoxometalates (POMs) show special advantages in inhibiting capacity attenuation, and good dispersion or combination of POMs with metal-organic frameworks (MOFs) is an important method to obtain high activity anode composites for LIBs. In this study, a uniform MoO2/MoS2 heterostructure with surface supported carbon (C-MoO2/MoS2) was successfully fabricated from a [Cu-2(BTC)(4/3)(H2O)(2)](6)[H3PMo12O40] precursor, which showed not only the designed octahedral morphology but also fast charge transfer, long working life, and high rate performance. Superior reversible lithium storage capacity of 1047 mA h g(-1) after 300 cycles was obtained at 1 A g(-1). Even after 700 cycles at 5 A g(-1), the discharge specific capacity of 646 mA h g(-1) was maintained, and rate capability of 610 mA h g(-1) could be achieved at 10 A g(-1). The high capacitive contribution could be explained by the relatively large specific surface area of porous C-MoO2/MoS2, which was mainly caused by the supported carbon network and MoS2 nanosheets, resulting in fast lithiation/delithiation processes.

Automated summary

By synthesizing the heterostructured material MoO2/MoS2 with a support of carbon (C-MoO2/MoS2), high-performance lithium-ion batteries with designed morphology, high capacity, and stability were achieved. The material exhibited excellent charge-discharge performance at different rates, showing great potential for practical applications.