Ag nanoparticles-decorated hierarchical porous carbon from cornstalk for high-performance supercapacitor. (July 2022)

• Record Type: Journal Article
• Authors: Wang, Rui; Li, Xinyi; Nie, Zhiguo; Jing, Qian; Zhao, Yang; Song, Hua; Wang, Huan
• Is Part Of: Journal of energy storage. Volume 51(2022)
• Publication Date: 2022-07
• Subjects: Biomass resource -- Porous carbon -- Ag nanoparticle -- Supercapacitor; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2022.104364
• Languages: English
• ISSNs: 2352-152X

Abstract

Abstract: In this work, hierarchical porous carbon is successfully synthesized by a simple carbonization approach using cornstalk as the precursor. And then the decoration of Ag nanoparticles (NPs) to cornstalk-derived porous carbon (CSPC) is further performed through an in-situ reduction reaction to obtain the composite material (CSPC-Ag). By using electron transport channels and active sites of Ag NPs to promote the diffusion of electrolyte ions, the CSPC-Ag electrode exhibits an improved specific capacitance. When the loading amount of Ag NPs on CSPC is optimized to be 5 wt%, the most outstanding electrochemical performance could be achieved that the specific capacitance was up to 323.8 F∙g −1 at 0.5 A∙g −1, which have 1.8 times enhancement compared to the undecorated CSPC. In addition, the CSPC-Ag electrode shows an excellent cyclic stability that the specific capacitance was only reduced by 6.8% after 4000 cycles at 10 A∙g −1 . Furthermore, the energy density of the CSPC-Ag based asymmetric supercapacitor reaches 15.9 Wh∙kg −1 at 11.2 kW∙kg −1 in the KOH electrolyte. Our work provides a facile strategy for developing high-performance Ag nanoparticles-decorated hierarchical porous carbon electrodes in supercapacitors as well as realizing the high value-added conversion and utilization of agricultural waste cornstalk. Highlights: Cornstalk-derived porous carbon decorated with silver nanoparticles enhanced the capacitance and stability of supercapacitor. High specific capacitance as 323.8 F/g was obtained in KOH aqueous solution with a wide potential window of 1 V for CSPC-Ag electrode. The electrode exhibited excellent specific energy of 15.9 Wh/kg with specific power of 11.2 kW/kg. Superb stability was shown by exhibiting capacitive retention of 93.2% for 4000 cycles.