Sustainable supercapacitors of sulfur-doped carbon from environmentally friendly sodium lignosulfonate impregnated...

The use of sustainable natural sources to fabricate porous carbon materials has garnered significant interest in energy storage. This study proposes a method for synthesizing sulfur-doped porous carbon (S‑carbon) materials via the carbonization of bacterial cellulose (BC) impregnated with sodium lignosulfonate (LS), which functions as a renewable source of both carbon and sulfur, eliminating the need for external activation processes. The carbonization process yielded S‑carbon with a notable sulfur content of 1.4 % and a high specific surface area of 650 m²/g. Transmission electron microscopy (TEM) images reveal fibrous carbon structures with mesopores and micropores in the S‑carbon material. Electrochemically, S‑carbon exhibited an impressive specific capacitance of 272.6 F g^-1 at a current density of 1 A/g and demonstrated outstanding cycling stability, retaining 86 % of its capacitance after 5000 cycles at a current density of 6 A/g in a 3 M KOH electrolyte. The development of sulfur-doped fibrous carbon from BC-LS offers promising potential as a sustainable electrode material for supercapacitors.