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

Here, we develop a hydrothermal method to grow Mn3O4 particles/gamma-MnOOH nanowires heterostructures simultaneously on carbon cloth (Mn3O4-gamma-MnOOH@CC) for high performance supercapacitor electrodes without any binder. The supercapacitor electrodes based on Mn3O4-gamma-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 Mn3O4-gamma-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 Mn3O4-gamma-MnOOH@CC electrode is a promising candidate for constructing high performance supercapacitors.