Few-layered WSe2 in-situ grown on graphene nanosheets as efficient anode for lithium-ion batteries

Highlights: • Hierarchical nanoarchitecture of WSe₂/RGO hybrid is synthesized. • Few-layered WSe₂ nanosheets are in-situ grown on conductive graphene nanosheets. • WSe₂/RGO hybrid exhibits much better electrochemical performance than bare WSe₂. • Excellent performance is attributed to the unique porous hierarchical structure. The hierarchical porous nanoarchitecture of WSe₂/reduced graphene oxide (WSe₂/RGO) hybrid, constructed by few-layered WSe₂ nanosheets in-situ grown on RGO nanosheets, has been synthesized through a facile one-pot solvothermal method. The WSe₂/RGO hybrid can be used as an efficient anode for lithium-ion (Li-ion) batteries and exhibits much better electrochemical performance than that of bare WSe₂: the WSe₂/RGO hybrid delivers a high initial discharge capacity of 744 mA h g⁻¹ at 0.2C and it remains 528 mA h g⁻¹ after 80 cycles, while the bare WSe₂ has a lower discharge capacity of 549 mA h g⁻¹ at 0.2C and it remains only 98 mA h g⁻¹ after 80 cycles; the WSe₂/RGO hybrid also demonstrates remarkably rate capability under different current rates from 0.2 to 8C. Those outstanding electrochemical performances of WSe₂/RGO hybrid can be assigned to its unique nanoarchitecture: the RGO nanosheets with high conductivity work as the skeleton of WSe₂/RGO anode facilitating the electron transfer; the RGO nanosheets can effectively prevent WSe₂ from the aggregation and promote the in-situ growth of WSe₂ layers on graphene, guaranteeing the formation of hierarchical porous nanoarchitecture with abundant electrochemically active sites, which can allow for efficient ionic diffusion and easy electrolyte infiltration. This study presents a rational-designed structure and facile strategy to fabricate transition metal dichalcogenides (TMDs)/graphene hybrid as promising anodes for lithium-ion batteries.