Binder-free electrodes based on Mn3O4/γ-MnOOH composites on carbon cloth for supercapacitor application

Abstract Here, we develop a hydrothermal method to grow Mn 3 O 4 particles/γ-MnOOH nanowires heterostructures simultaneously on carbon cloth (Mn 3 O 4 -γ-MnOOH@CC) for high performance supercapacitor electrodes without any binder. The supercapacitor electrodes based on Mn 3 O 4 -γ-MnOOH@CC exhibit outstanding electrochemical performance. In three-electrode system measurement, a specific areal capacitance of 2507.1 mF cm −2 at a current density of 1 mA cm −2 is achieved. When the current density increases to 10 mA cm −2 , a specific areal capacitance of 1365.2 mF cm −2 is still kept. We also fabricate a symmetric supercapacitor device by using Mn 3 O 4 -γ-MnOOH@CC, demonstrating a specific areal capacitance of 1201.2 mF cm −2 and a high energy density of 1.47 mWh cm −3  at a current density of 3 mA cm −2 . The cyclic stability test shows that the capacitance retention is 92.6% after 10000 cycles. These remarkable results indicate that Mn 3 O 4 -γ-MnOOH@CC electrode is a promising candidate for constructing high performance supercapacitors.