Nitrogen-Doped Porous Carbon Nanospheres from Natural Sepia Ink: Easy Preparation and Extraordinary Capacitive Performance

摘要

Heteroatom-doped nanostructured porous carbons have attracted intensive attention for electrical-double layer capacitors(EDLCs) because of their large surface area and surface functionalization. Here we use biowaste sepia ink as a sustainable source to synthesize nitrogen-doped highly porous carbon nanospheres by a simple molten salt-based activation strategy. The introduction of molten salt is not only beneficial for repairing the carbon conjugate network, but can also further improve the activation effect of porogen. The as-obtained carbon nanospheres (MA-NCS) displayed a large surface area of 1760m(2)g(-1), optimized pore architecture, and high nitrogen content (8.6wt%). With this design, the MA-NCS as EDLCs electrode exhibited a remarkable specific capacitance of 320Fg(-1) at the current density of 0.5Ag(-1) and high rate capability in 6m KOH electrolyte. Furthermore, the assembled EDLCs demonstrated a high specific capacitance of 130Fg(-1) at 0.5Ag(-1) in an organic electrolyte (1m TEABF(4)/AN), obtaining a maximum energy density of 28.2Whkg(-1) at a power density of 625Wkg(-1). This novel biowaste precursor-synthesis route presents great potential for facile large-scale production of high-performance porous carbons for green and long-term energy storage.