CuCo<sub>2</sub>O<sub>4</sub>/NiCo-Metal–Organic Framework Nanoflake Arrays for High-Performance Supercapacitors
Wuxing Ji, Jiao–Jiao Zhou, Peilin Zhang, Wanqing Wang, Xicheng Xu, Yang Yang, Hualong Ding, Weiwei Wang, Le Xu, Luyang Chen
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.