Albumen-Derived Hierarchical Porous N- and O-Enriched Carbon towards High-Performance Electrochemical Capacitors

Abstract

In the work, we developed a facile yet scalable fabrication of N- and O-enriched carbon with hierarchical micro-/mesopores from common agricultural-derived chicken albumen. The albumen-derived hierarchical micro-/mesoporous carbon (AHMC) was endowed with large specific surface area (SSA, 1227 m2 g−1), hierarchical porosity with high microporosity of ∼50.7%, and high content of heteroatom functionalities (∼2.7 at% N and ∼20 at% O). Thanks to hierarchical micro-/mesoporosity, large effective SSA, and remarkable heteroatom (N, O) doping effects, i.e., the prominent synergy of the structural and compositional advantages, the resultant AHMC delivered a high specific capacitance (SC) of 329 F g−1 at 0.2 A g−1, and even 175 F g−1 at large current rate of 10 A g−1. The high SC retention of ∼93.3% over continuous 5000 cycles further highlighted promising advantages of the AHMC for long-term ECs. More remarkably, a striking energy density of ∼6.1 Wh kg−1 was obtained for the AHMC-based aqueous symmetric device with 1 M H2SO4 electrolyte.