Sustainable nitrogen-containing hierarchical porous carbon spheres derived from sodium lignosulfonate for high-performance supercapacitors

Nitrogen-containing carbon sphere with hierarchical porous structure is obtained through a facile thermostabilization and carbonization method of biomass-derivative sodium lignosulfonate. The synthesis route we proposed is cost-effective and environment-friendly without additional nitrogen precursor, activation or templating agent. The as-prepared carbon spheres exhibit high specific surface area of 1255–1939 m2 g−1 and moderate surface nitrogen...