Nitrogen-doped activated carbons via melamine-assisted NaOH/KOH/urea aqueous system for high performance supercapacitors

NaOH/urea, a cellulose solvent, has been applied for the preparation of binderless and in situ N-dopedGACs (NaOH/urea-GACs). The dissolved cellulose binds lignin, hemicellulose and undissolved celluloseall together to form a granular precursor after kneading and extruding. During the process, NaOH andurea are dispersed in sawdust where the NaOH acts as an activator at high temperatures, and the ureaplays the role of an in situ N-dopant. The results show that at a mass concentration ratio of 14 wt%NaOH/24 wt% urea which has been activated for 1 h at 850 ℃ after kneading for 2 h GACs witha specific surface area (SBET) of 811.299 m2 g 1, a microporosity of 59.20% and an abrasion resistance of99.83% are obtained. The N content as well as its form of existence are also further explored.