Synthesis of Ni 4 Yb(OH) 10 NO 3 ⋅ 3H 2 O Nanosheets for Electrode Materials in Electrochemical Energy Storage

Transition metal hydroxides have attracted considerable attention as promising electrode materials in electrochemical energy storage. In this work, we first used a facile and green approach to synthesize Ni 4 Yb(OH) 10 NO 3  ⋅ 3H 2 O nanosheets, which are thin‐layer hexagonal structures. Additionally, this method can be developed to synthesize other lanthanide‐doped Ni(OH) 2 materials. When used as electrode materials, these nanosheets exhibited excellent electrochemical energy storage performance and good cycling stability. For example, the Ni 4 Yb(OH) 10 NO 3  ⋅ 3H 2 O nanosheet electrode showed a specific capacitance of 1482.1 F g −1 at 1 A g −1 , while maintaining great cycling stability (a capacity retention of 71.8 % after 2000 cycles at a current density of 1 A g −1 ).