High-rate asymmetrical supercapacitors based on cobalt-doped birnessite nanotubes and Mn-FeOOH nanotubes

Herein, we firstly prepared Co-doped birnessite and Mn-FeOOH nanotubes by a simple hydrothermal process using a sacrificed template method. The doping ratio was adjusted by setting the molar ratios of Co and Mn in the preparing process. Both the Co-doped birnessite and Mn-FeOOH nanotubes exhibit ideal electrochemical properties, especially their excellent rate capability.