N,O-Codoped Hierarchically Porous Carbons Derived from Squid Pen for High-Capacity Supercapacitors

Fabrication of multi-heteroatom doped hierarchically porous carbon with a facile and environment procedure has been well investigated for supercapacitor industry. We put forward a time-saving and environmentally friendly method for the manufacture of N,O-codoped carbons by using direct carbonization of biomass squid pens. Under our facile procedure, the raw carbon materials have been transformed into hierarchical porous carbons, combined with high specific area surface (2540 cm(2).g(-1)), micro/meso/macropore inside, and rich N (1.01-7.44%) and O (17.00-18.88%) content. It is a completely novel and green avenue for constructing hierarchical porous carbon materials from biomass, showing large commercial potential. Supercapacitors made from the resulting material possess very high specific capacitance (the highest up to 581 F.g(-1)), twice as much as commercial activated carbon (100-250 F.g(-1)). In particular, it retains 336.6 F.g(-1) of specific capacitance at a high current density of 10 A.g(-1), which is a promising material for devices that require operation at high current densities. In addition, it also has a high cyclic stability (maintaining 90% capacitance after 10,000 cycle) and lower impedance. We believe that the hierarchically porous N,O-codoped carbons derived from squid pens could be an ideal candidate for the energy storage and conversion devices.