Preparation of Nitrogen and Sulfur Co‐doped and Interconnected Hierarchical Porous Biochar by Pyrolysis of Mantis Shrimp in CO2 Atmosphere for Symmetric Supercapacitors

Abstract A porous functional biochar (MSCs) rich in N and S heteroatom doping was prepared by pyrolyzing mantis shrimp shells as the biomass source of the typical processing seafood waste in CO 2 atmosphere. The physical and chemical properties of carbon materials were adjusted by the control of the pyrolysis temperature. In this study, maximum specific surface area (SSA) and pore volume of 484.5 m 2 g −1 and 0.291 cm 3 g −1 , respectively of the MSCs material were reached at 700 °C. Moreover, it was found in the characterization test that heteroatoms, such as N and S were successfully introduced into the carbon microstructure. MSC‐750 contains N of up to 9.46 % and 0.52 % of S. Although its SSA is only 431.6 m 2 g −1 , the specific capacitance of the 6 M KOH symmetrical supercapacitor at 1 A g −1 reaches the maximum value of 144.2 F g −1 among all samples due to the pseudocapacitance generated by its high content of heteroatomic functional groups.