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We herein report a facile two‐pot method to prepare a series of the two‐dimensional Ni(OH)2 nanocrystals with varied surface structures via the in‐situ surface transformation derived from Nickel metal‐organic framework (Ni‐MOF) in KOH solution at room temperature. The Ni(OH)2 obtained at the KOH concentration of 0.25 M displayed superior performance among the samples in terms of activities and stability. Further investigation proves that the enhanced urea oxidation reaction (UOR) activities can be ascribed to the cooperation of the larger electrochemical surface area, a faster electronic transfer speed, and a lower transfer resistance on the surface. These findings provide a new route for the rational design and synthesis of advanced electrocatalysts with relatively lower energy consumption that aims to be large‐scale synthesized and utilized in clean energy conversion and applications. [ABSTRACT FROM AUTHOR]

The development of low-cost electrode materials with enhanced activity and favorable durability for hydrogen evolution reactions (HERs) is a great challenge. MoS2 is an effective electrocatalyst with a unique layered structure. In addition, aluminosilica shells can not only provide more hydroxyl groups but also improve the durability of the catalyst as a protective shell. Herein, we have designed a hard-template route to synthesize porous yolk–shell MoS2@void@Aluminosilica microspheres in a NaAlO2 solution. The alkaline solution can directly etch silica (SiO2) hard templates on the surface of MoS2 microspheres and form a porous aluminosilica outer shell. The electrocatalytic results confirm that the MoS2@void@Aluminosilica microspheres exhibit higher electrocatalytic activity for HERs with lower overpotential (104 mV at the current density of −10 mA cm−2) and greater stability than MoS2 microspheres. The superior electrocatalytic activity of MoS2@void@Aluminosilica microspheres is attributed to the unique structure of the yolk@void@shell geometric construction, the protection of the aluminosilica shell, and the greater number of active sites offered by their nanosheet subunits. The design of a unique structure and new protection strategy may set up a new method for preparing other excellent HER electrocatalytic materials. [ABSTRACT FROM AUTHOR]