Abstract
? 2022 Elsevier B.V.Designing bimetallic sulfide materials with well-defined nanostructure and high energy density is indeed desirable for high-performance supercapacitors. Here, a hollow zinc cobalt sulfide (ZnxCo3?xS4) dodecahedron with plentiful sulfur vacancies is synthesized through a co-precipitation approach followed by a solvothermal vulcanization treatment. The tailored hollow structure can effectively accelerate the charge transport and facilitate the diffusion of OH-, whereas the sulfur vacancies significantly increase the amount of contact active sites and enhance the electronic conductivity. Both of the features can simultaneously promote the capacitance performance of ZnxCo3?xS4 for supercapacitors, where the most-performing Zn0.3Co2.7S4 electrode, achieves a high specific capacitance of 545.9 C g?1 in 3 M KOH electrolyte at the current density of 1 A g?1 and excellent long-term durability of 84.7% capacity retention after 1000 cycles. Particularly, the assembled aqueous hybrid supercapacitors delivers high energy density and superior cyclic stability. This study demonstrates a rational design of well-controlled bimetallic sulfides with outstanding electrochemical performance for energy storage devices.
NSTL
Elsevier