MOF derived hierarchical ZnNiCo-LDH on vapor solid phase grown Cu_xO nanowire array as high energy density asymmetric supercapacitors

Construction of a high energy density electrode for supercapacitors is crucial, but balance between stable structure and efficient electron transfer is still ambiguous. In this work, a metal organic framework (MOFs) derived leaf like hierarchical ternary layered double hydroxide (ZnNiCo-LDH) was integrated with the in-situ grown copper oxide (Cu_xO) nanowire arrayed on Cu-foam. In the ZnNiCo-LDH/CuO-Cu, integrated two sheet-wire components could mediate the large surface electronic structure to improve intrinsic charge transport and offer more abundant electroactive sites for redox reaction. The ZnNiCo-LDH/CuO-Cu exhibited a high specific capacity of 378.10 mA h g⁻¹ at 1 A g⁻¹, remarkable rate capability and outstanding cyclic stability, superior to CuO-Cu. The admirable electrochemical performance of the ZnNiCo-LDH/CuO-Cu can be attributed to the distinctive CuO nanowires grown on conductive substrate and strong synergistic effects of zinc, cobalt, and nickel ions. Furthermore, an asymmetric supercapacitor (ASCs) device was assembled with ZnNiCo-LDH/CuO-Cu cathodes and MOFs derived N-CNT as anode, which delivered high energy density of 117.5 Wh kg⁻¹ at the power density 576.9 W kg⁻¹ and excellent stability; this outperforms favorably with analogous supercapacitors. It is anticipated that the rational design of ZnNiCo-LDH/CuO-Cu will endow new possibilities for the rational design of highly functional MOFs derivatives in the field of energy storage.