Electrodeposition of manganese dioxide film on activated carbon paper and its application in supercapacitors with high rate capability

In this research magnesium dioxide (MnO 2 ) is electrodeposited over activated carbon paper (ACP) to form a composited MnO 2 /ACP material. The as-prepared MnO 2 /ACP shows excellent capacitance performance with a high specific capacitance of 485.4 F g −1 calculated from a discharge curve with current density 2.0 A g −1 , owing to its enlarged specific surface area and improved electronic conductivity. Moreover, the MnO 2 /ACP possesses remarkable rate capability due to the easy access of electrolytic ions, leading to complete utilization of MnO 2 active material for supercapacitors. To summarize, the electrodeposition of MnO 2 thin film on activated carbon paper is reported for the first time, and the composited MnO 2 /ACP is a promising electrode material for building up efficient supercapacitors. The composite MnO 2 /ACP is reported for the first time and it shows high specific capacitance and remarkable rate capability.