Design and Synthesis of a Reduced Graphene Oxide/Patronite Composite with Enhanced Lithium-Ion Storage Performance

The construction of graphene-based composites is a novel electrode material design strategy and has become a promising field in new energy material research. However, the rational design principle is still poorly understood, and the synthetic technology urgently needs to be expanded. Here, a novel strategy for the synthesis of a reduced graphene oxide (rGO)/VS₄ nanoparticle (NP) composite is reported using an ionic liquid (IL)-assisted hydrothermal method. The synergistic effects of graphene and IL, which include the π-cation/anion interactions of graphene, the capping agent effect of IL, and their π-π stacking interaction, are responsible for the synthesis of the composite, achieving delicate tailoring of VS₄ NPs as well as their homogeneous dispersal on the surface of rGO nanosheets. The superior nanostructure of the composite results in enhanced lithium-ion storage performance, such as improved cyclic stability (1009 mA h g^-1 at 0.1 A g^-1 after 150 cycles and 788 mA h g^-1 after 240 cycles even at 1 A g^-1) and rate capability (1540 and 621 mA h g^-1 at 0.1 and 2 A g^-1, respectively). This strategy provides an effective new approach for designing graphene composites and is expected to be applicable in the design of other rGO/transition-metal sulfide composites for energy storage.