Hierarchical NiMn Layered Double Hydroxide/Carbon Nanotubes Architecture with Superb Energy Density for Flexible Supercapacitors

A hierarchical nanostructure composed of NiMn‐layered double hydroxide (NiMn‐LDH) microcrystals grafted on carbon nanotube (CNT) backbone is constructed by an in situ growth route, which exhibits superior supercapacitive performance. The resulting composite material (NiMn‐LDH/CNT) displays a three‐dimensional architecture with tunable Ni/Mn ratio, well‐defined core‐shell configuration, and enlarged surface area. An electrochemical investigation shows that the Ni 3 Mn 1 ‐LDH/CNT electrode is rather active, which delivers a maximum specific capacitance of 2960 F g –1 (at 1.5 A g –1 ), excellent rate capability (79.5% retention at 30 A g –1 ), and cyclic stability. Moreover, an all‐solid‐state asymmetric…