Superb Electrolyte Penetration/Absorption of Three-Dimensional Porous Carbon Nanosheets for Multifunctional Supercapacitor

High specific surface area and reasonable pore-size distribution are conducive to promote the energy density and power density of carbon based supercapacitors. Nevertheless, the permeability of electrolyte is a prerequisite condition for surface storage charge and the ion diffusion in multiscale pores. Therefore, improving the electrolyte penetration/absorption is particularly important. Herein, we reported a novel three-dimensional porous ultrathin carbon nanosheet (3DPAC) with considerable electrolyte penetration/absorption property, which was proven by experiment and theory. The 3DPAC was prepared from abundant biomass waste wood dust via hydrothermal and carbonized treatment and characterized with ultrathin nanosheets, abundant porous structure, and rich N, O dopant. This unique three-dimensional and hierarchical porous structure leads to robust conduction of electrons and the penetration/absorption of electrolyte ions, which endow the 3DPAC with approved electrochemical properties. The supercapacitor based 3DPAC shows satisfying energy density (79.4 Wh/kg) and power density (5.1 kW/kg), and impressive cyclic stability with 94.6% after 5000 charge/discharge processes. More amazing, the soft-packaged supercapacitor presents stable electrochemical behaviors at multiple folding states and low pressure environment. Therefore, this meaningful research will open a brand-new direction to devise and prepare state-of-art porous carbon materials for high-performance supercapacitors applied in complex environments.