CuCo₂O₄/NiCo-Metal–Organic Framework Nanoflake Arrays for High-Performance Supercapacitors

Abstract

Developing hybrid metal–organic frameworks (MOFs) with ordered structure is significant to obtain promising electrode materials for supercapacitors. Herein, the special electrodes of CuCo2O4/NiCo-MOF nanoflake vertical arrays are constructed on Ni foam by using the CuCo2O4 nanorods as a self-sacrifice template. Because of the multidirectional interconnected channels of spinel CuCo2O4, great electrochemical activity of NiCo-MOF, well-arranged morphology, and synergy effect at the interface, the resulting CuCo2O4/NiCo-MOF nanoflakes exhibit remarkable specific capacity (12.81 F/cm2 or 1423 F/g at 2 mA/cm2) and excellent rate performance (remaining 79.2% at 30 mA/cm2). The asymmetric supercapacitor assembled by CuCo2O4/NiCo-MOF and an activated carbon electrode shows excellent energy density of 0.48 mWh/cm2 at a power density of 1.50 mW/cm2. This work inspires insight into exploiting hybrid MOFs with highly aligned arrays for energy storage.