Bacterial cellulose-derived porous carbon aerogel containing FeS as the self-supporting anode for high-efficiency lithium-ion storage

Abstract

Lithium-ion hybrid capacitors (LIHCs) attract extensive attention because of the urgent demands for high-energy density and high-power density devices. Here, a free-standing FeS@C/carbonized bacterial cellulose aerogel (FeS@C/CBC) -based anode for LIHCs is developed by growth of MIL-88-NH2 on bacterial cellulose (BC) substrate, followed by simultaneous carbonization and sulfidation. The obtained FeS@C/CBC inherits the three-dimensional, highly porous structure, and free-standing properties of CBC. FeS is uniformly distributed in the nitrogen-rich carbon and tightly deposited on the CBC fibers, and such structure favors a fast Li/e− transport. As a result, the free-standing FeS@C/CBC delivers a high reversible capacity of 669 mAh g−1 after 1000 cycles at 1 A g−1. Additionally, when the obtained anode is combined with the KCBC as the cathode, the resulting full cellulose-based cell exhibits an impressive cycling stability with the capacity retention of 77.8 % over 10,000 cycles at 5 A g−1 and a high energy density of 172 Wh kg−1 within the voltage window of 0.01–4.2 V, demonstrating a promising potential for practical applications in the field of LIHCs.