•Co3O4/C@MoS2 core-shell materials are prepared and used as supercapacitor electrodes.•ZIF-67 is used as the sacrificial templates and the precursors for Co3O4/C.•Co3O4/C@MoS2 shows excellent capacitive performances and cyclic stability.•This work opens a window to design MOF-based materials used in energy storage system.Hierarchical mesoporous Co3O4/C@MoS2 core-shell structured materials are synthesized via a two-step calcination and a solvothermal method using cobalt metal-organic frameworks (cobalt-MOFs, ZIF-67) and (NH4)2MoS4 as the precursors of Co3O4/C and MoS2, respectively, which is a new class of core-shell materials as supercapacitor electrode materials. The obtained Co3O4/C@MoS2 exhibits high specific capacitance (1076 F g−1 at 1 A g−1), rate capability (76.9% capacitance retention at 10 A g−1) and cyclic stability (64.5% capacitance retention after 5000 cycles at 10 A g−1). Moreover, the content of MoS2 greatly influences the electrochemical performances of the obtained core-shell materials. The results demonstrate that the as-synthesized ZIF-67 can be used as a promising candidate for designing Co3O4 based core-shell materials used in supercapacitors.Download high-res image (216KB)Download full-size image

•Electrochemical recognition of Trp isomers at self-assembled diphenylalanine (FF) structures.•The FF structures depend on the material used to induce self-assembly.•This is the first example of a chiral platform constructed with simple building blocks.Molecular self-assembly offers a promising route to the preparation of advanced materials for the construction of novel chiral sensing devices, and the inspiration for the development of such systems is often derived from simple biological models. Diphenylalanine (FF), an extensively studied short peptide, can self-assemble into highly ordered nano-/micro-structures. Here we report the electrochemical recognition of tryptophan enantiomers using three FF self-assembled structures produced in the presence of graphene quantum dots (GQDs), chitosan (CS) and cetyltrimethylammonium bromide (CTAB). Although the difference in the peak potentials of the enantiomers is very small, enantiomeric differences can be detected by the magnitude of the DPV current signals. The recognition efficiencies of the three self-assembled materials are different, due to the different structures formed during the self-assembly process.Download high-res image (252KB)Download full-size image