In-situ construction of hierarchical structure with 1D MnCo2S4 interpenetrate 3D Co9S8 hollow polyhedrons towards high performance hybrid supercapacitors

Obtaining high-capacity electrode materials is a key problem to be solved for high performance supercapacitors. Metal-organic frameworks derivatives have been considered to be ideal electrodes due to their large specific surface area and pore connectivity. Herein, we design a novel controllable structure, in which MnCo2S4 nanorods with one-dimensional structure are inserted into three-dimensional ZIF-67 derived Co9S8 hollow polyhedrons, the ratio between the two substances can be effectively regulated by controlling the reaction time. Among them, MC-3 sample shows the best performance and its capacity can reach up to 1058.0 F g−1 (146.9 mA h g−1) at 1 A g−1. A supercapacitor constructed by MC-3 as the positive electrode, using activated carbon as the negative electrode, the assembled device shows a high energy density of 35.8 W h kg−1 at 750 W kg−1. Besides, the supercapacitor also shows a steady cycling capacity of 82.1% retention after 6000 cycles. The excellent performance of the hybrid supercapacitor could envision promising applications in future high-performance energy storage devices.