Dual metal MOF derived Co-Ni/rGO as cathode material with synergetic effect for an asymmetric supercapacitor with enhanced performances
Honglu Wu, Shuang Li, Yang Liu, Qing Mu, Yixiang Shi
Abstract
Transition metal oxide/hydroxide possesses high theoretical capacity by inducing faradaic processes . However, it is facing the challenges associated with using individual transition metal oxide/hydroxide as an electrode material for supercapacitors . Specifically, the depletion of the metal upon exposure to the electrolyte during cycling processes leads to poor performance. To address this issue, a novel Co Ni alloy, derived from bi-metal organic frameworks (MOFs), intercorporate with rGO nano-sheet was synthesized as an electric conductive network. This Co-Ni/rGO composite exhibited high performances with a specific capacitance of 5229.5 F g −1 at 1 A g −1 , and 81.3 % capacitance retention after 1300 charge-discharge cycles at 10 A g −1 . Additionally, the composite was also used as a cathode in an asymmetric supercapacitor configuration alongside an rGO aerogel anode, resulting in an energy density of 39.58 and 14.38 W h kg −1 at power densities of 208.3 and 20,833.33 W kg −1 . The device showed an 87.4 % capacitance retention after 10,000 cycles at a current density of 10 A g −1 , highlighting the potential of this composite for future energy storage applications .