Amorphous MoO2 nanostructures are regarded
as promising
anode materials for lithium-ion batteries (LIBs) due to their unusually
high capacity. However, designing an amorphous MoO2 nanostructure
with satisfactory performance still remains greatly challenging owing
to the poor conductivity and unstable structure. In this study, a
hierarchically porous composite composed of amorphous MoO2/C nanospheres and interconnected graphene networks (MoO2/C-rGO) was fabricated by a convenient route. Thanks to the oxygen-deficient
amorphous nanostructure, open diffusion channels, and continuous conductive
networks, the electrochemical performance of the composite has been
significantly enhanced. Specifically, it delivers an extraordinary
initial discharge capacity of 1328 mA h g–1 at 0.1
A g–1, a high initial Coulombic efficiency (CE)
of 82.6%, an impressive rate capability of 444 mA h g–1 at 8.0 A g–1, and a good cyclability with 642
mA h g–1 after 500 cycles at 1.0 A g–1. Electrochemical analysis indicates that the Li storage of MoO2/C-rGO is dominated by a pseudocapacitive mechanism, which
allows rapid insertion/extraction of Li+ without damaging
the structure of the electrode, thus achieving structural and electrical
integrity.