Superior electrochemical performance of carbon cloth electrode-based supercapacitors through surface activation and nitrogen doping

A simple and low-cost strategy is developed to fabricate three-dimensional (3D) nitrogen-doped carbon cloth electrode through surface activation and nitrogen-doping process. The process can exfoliate the smooth surfaces of micro carbon fibers into nanostructures together with the doping of nitrogen-containing species. The as-fabricated carbon cloth electrode shows excellent areal capacitances of 882.36 and 706.68 mF cm(-2) at the current density of 1 and 60 mA cm(-2), respectively, exhibiting good rate performance. It also exhibits outstanding cycling stability with 98.7 % retention of its initial capacitance after 30,000 continuous charging/discharging tests. When the electrodes were assembled and tested as a symmetric supercapacitor, it also demonstrates superior electrochemical performance. It is believed that the 3D carbon structures with enlarged surface area, improved conductivity and electrode/electrolyte wettability, and enhanced pseudocapacitance by doping of nitrogen lead to the vast improvement of electrochemical performance.