Multi-channeled hierarchical porous carbon incorporated Co3O4 nanopillar arrays as 3D binder-free electrode for high performance supercapacitors

Abstract

3D hierarchical carbon-based nanostructures not only create hierarchical porous channels, but also possess high electrical conductivity and maintain excellent structural mechanical stability for high-performance supercapacitors. In this research, hierarchical porous N-doped carbon and Co3O4 nanopillar arrays derived from Morpho butterfly wing scales have been explored. These structures have demonstrated enhanced capacitance, with a maximum specific capacity of 978.9Fg−1 at 0.5Ag−1, and good cycling stability, retaining about 94.5% of their capacitance after 2000 cycles as well as improving supercapacitor energy density without sacrificing power density. The maximum energy density of the carbonized wing scale-cobalt oxide (CWs-Co3O4) composite supercapacitors was found to be 99.11Whkg−1. This paper proposes a method for building 3D hierarchical N-doped carbon materials with various morphologies. It also presents a concept and method for designing a carbon-based 3D binder-free electrode with a hierarchical structure. This research provides a vast structural pool for developing novel electrochemical properties based on these materials.