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Constructing hierarchical core‐shell configuration from well‐known metal sulfides is one way to further tune and utilize unique species. Herein, a novel core‐shell structure is developed based on CoS deposited on NiS nanosheets, which involves hydrothermal and electrodeposition method. The micromorphology of the composite electrode can be optimized by adjusting the cycles of electrodeposition. Taking advantages of the highly conductive, open framework of the core‐shell nanolayer, the 5‐NiS@CoS electrode shows a specific capacitance of 1210 F g−1 at a current density of 1 A g−1 (retaining 82% from 1 to 10 A g−1, while NiS substrate is only 39%). The specific capacitance retention rate is 80.94% at 10 A g−1 after 2000 cycles (NiS substrate is 59.6%). Moreover, NiS@CoS//AC asymmetric supercapacitor device delivers an energy density of 24.1 Wh kg−1 at a power density of 752.15 W kg−1 and remarkable stability (over 80% retention after 5000 cycles). This work may prompt the exploration of the synthesis of inexpensive compounds incorporating highly reactive components for supercapacitors.

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A typical flow field plate of proton exchange membrane fuel cells has a distribution zone that connects the input ports and main channel region where major reactions take place. In this study, the effects of two distribution zone designs, i.e., the channel-ridge distribution zone (CRDZ) and dot matrix distribution zone (DMDZ), on the gas distribution uniformity and pressure drop are investigated numerically. For the flow fields with CRDZ, the theoretical mass flow rates and pressure distributions are found to agree with numerical results well. The flow rate distributions in the flow fields become more uniform when the turning angle increases to special angle. To design the flow fields with CRDZ, the channels can be arranged with simple geometry lines in the first step and then optimised with CFD considering the actual size to achieve a more uniform distribution and suitable pressure drop. For the flow fields with DMDZ, the uniformity of gas distribution depends on the shunt and dispersion effects of dot matrix, and the rectification and expansion effects of the distribution chamber. With an increase in porosity of DMDZ, the gas distribution gets better, and it is the most uniform when the distribution zone is an empty chamber.