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It is of significant urgency to fabricate highly active catalysts for electro‐oxidation of hydrazine for application in direct hydrazine fuel cells (DHFCs). Thus, in this work we grow three‐dimensional (3‐D) α‐Co(OH)2 thin‐layered cactus‐like nanostructures (shell) on the surface of Ni3S2 nanowires (core) enveloped nickel (Ni) foam substrate. HRTEM images clearly reveal that the α‐Co(OH)2 thin‐layered cactus‐like nanostructures (shell) are evenly surrounded on the surface of Ni3S2 nanowires (core). Notably, α‐Co(OH)2/Ni3S2 thin‐layered cactus‐like nanowires modified Ni foam displays an enhanced electro‐oxidation of hydrazine (340 mA current response and the onset oxidation potential of −1.10 V) than α‐Co(OH)2 sponge‐like, and Ni3S2 nanowire structures. The obtained enhanced electro‐catalytic response is mainly due to its electron rich Ni active centers, larger electrochemically active surface area, higher electrical conductivity, and porous surface‐structure formed by growing α‐Co(OH)2 thin‐layered cactus‐like nanostructures on the Ni3S2 nanowires, henceforth increasing the inherent activity and the number of available active sites/spots. Further, the α‐Co(OH)2/Ni3S2 thin‐layered cactus‐like nanowire catalyst shows notable stability (stable for more than a week) towards electro‐oxidation of hydrazine. Thus, as fabricated cactus‐like thin‐layered α‐Co(OH)2/Ni3S2 core‐shell nanowires catalyst can be considered as potential and robust catalyst for electro‐oxidation of hydrazine.

Fuel cells are eco-friendly energy devices with high efficiency. They are regarded as ideal power sources, especially for hybrid vehicles with rechargeable batteries. In this study, we proposed the parameters for the optimal hybrid ratio of a fuel cell hybrid electric vehicle (FCHEV). We made a model FCHEV with fuel cells and rechargeable batteries (Li-ion batteries) and carried out various tests to obtain parameters for several driving conditions. These parameters are used to find the optimal ratio of the power of the fuel cells to the total power (power of fuel cells + power of rechargeable batteries). The results indicate that the optimal hybrid ratio is 0.4. In this case, the powers from the fuel cells and rechargeable batteries are about 50 and 70 kW, respectively. The optimal parameters in this study can be used to develop power transmission systems of FCHEVs. The results of this study are expected to improve FCHEVs to become an important means of mass transportation.