Multi-heteroatom self-doped porous carbon derived from swim bladders for large capacitance supercapacitors

Abstract

Multi-heteroatom self-doped porous carbon was synthesized via carbonization and activation of amino-acid-rich swim bladders and used for high-performance supercapacitors. The effects of different activation temperatures on the pore structure and composition of the carbon were investigated by TEM, Raman, XPS and nitrogen sorption analyses. With increasing temperature, the pore size broadens and the amount of doped heteroatoms decreases. The obtained materials have a high surface area of up to 3068 m² g⁻¹ with nitrogen, oxygen and sulfur multi-heteroatom doping. Carbon activated at 550 °C shows the highest capacitance of 410 F g⁻¹ and excellent cyclic stability during 10 000 cycles due to the high surface area and multi-heteroatom doping. The outstanding performance makes this material promising for supercapacitors.