Application of Biomass-Derived Nitrogen-Doped Carbon Aerogels in Electrocatalysis and Supercapacitors

Biomass-derived carbon aerogels refer to carbon aerogels prepared using biomass as the precursor. They are environmentally friendly, cheap and have abundant precursors, which have aroused widespread interest and exhibit excellent performance in the fields of electrocatalysis (e. g. for the hydrogen evolution, oxygen evolution and oxygen reduction reactions) and energy storage (i. e. as electrode materials for supercapacitors). Furthermore, metal species can be incorporated into the porous carbon matrix without destroying the original 3D structure whilst improving its conductivity and electrochemical performance. Above all, most biomass materials contain nitrogen functionalities, and can be doped in situ (self-doping) with heteroatoms, such as N, without any additives, thereby creating additional defects and active centers with augmented electron density and electron-contributing attributes. Herein, the electrochemical applications of biomass-derived carbon aerogels reported during the last decade, especially in the field of water electrolysis, metal-air batteries, fuel cells and supercapacitors, are summarized. Current research challenges and future directions are briefly highlighted.