Growth of manganese oxide nanoflowers on vertically-aligned carbon nanotube arrays for high-rate electrochemical capacitive energy storage.

Manganese oxide nanoflower/carbon nanotube array (CNTA) composite electrodes with hierarchical porous structure, large surface area, and superior conductivity was controllable prepared by combining electrodeposition technique and a vertically aligned CNTA framework. This binder-free manganese oxide/CNTA electrode presents excellent rate capability (50.8% capacity retention at 77 A/g), high capacitance (199 F/g and 305 F/cm (3)), and long cycle life (3% capacity loss after 20,000 charge/discharge cycles), with strong promise for high-rate electrochemical capacitive energy storage applications.