Precisely tailored morphology of polyimine for simple synthesis of metal sulfide/carbon flower-like superstructures

Metal sulfide/carbon superstructures are a new class of functional materials for various energy applications due to their strong synergistic effect and favorable geometry. However, developing a controllable way to synthesize metal sulfide/Carbon superstructures with high N doping , well-designed 3D superstructure and refined metal sulfide nanoparticles remains a big challenge. Herein, we report a one-pot synthesis of metal sulfide/carbon flower-like superstructures (M x S y /CFSs) by using metal ion doped polyimine. The morphology of polyimine can be easily tuned by choosing different solvents or different amino monomers . The presence of imine bond and thiophene in polyimine not only can coordinates with metal ion and transforms them into metal sulfide during carbonization , but also provides high N and S doping for the M x S y /CFSs. Benefiting from the advantages of these structures, multiple M x S y /CFSs (such as FeS/CFSs, Co 9 S 8 /CFSs, Ni 3 S 2 /CFSs, and MnS/CFSs) with high N doping , uniform metal sulfide nanoparticles and hierarchical superstructures were fabricated by directly carbonizing metal ion doped polyimine flower-like superstructures in nitrogen atmosphere. The as-prepared Co 9 S 8 /CFSs exhibits superior sodium storage properties with stable cycling performance and excellent rate capacity. This new finding provides a novel strategy to controllably design and produce metal sulfide/carbon flower-like superstructures for the applications in energy storage.