High-energy-density on-chip supercapacitors using manganese dioxide-decorated direct-prototyped porous carbon electrodes

High performance on-chip micro supercapacitors are presented, using manganese dioxide (MnO₂) decorated into direct prototyped porous carbon electrodes. By incorporating MnO₂ into carbon framework, both electric double layer capacitance (EDLC) and pseudocapacitance contribute to total capacity. The configuration is realized by combination of nano template into photolithography technology, carbonization, removing the template to form patterned porous carbon network, and designed electrochemical deposition process to grow MnO₂ in the carbon framework. The capacitance of the composite increases compared with pure porous carbon without obvious decay in cycle life. Then the on-chip prototypes using the composite as electrode material are designed and the volumetric capacitance of 2.9mF/(cm² μm) under the scan rate of 50mV/s is much higher than 0.8mF/(cm² μm) of carbon.