Converting biowaste corncob residue into high value added porous carbon for supercapacitor electrodes. (August 2015)

• Record Type: Journal Article
• Authors: Qu, Wen-Hui; Xu, Yuan-Yuan; Lu, An-Hui; Zhang, Xiang-Qian; Li, Wen-Cui
• Is Part Of: Bioresource technology. Volume 189(2015)
• Page Start: 285
• Page End: 291
• Publication Date: 2015-08
• Subjects: Biowaste -- Corncob -- Porous carbon -- Supercapacitor; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2015.04.005
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: A high value added porous carbon was obtained from a corncob residue, which shows a superior capacitive performance compared to those polymer-based synthetic carbons as electrode material for a supercapacitor. The corresponding symmetrical cell shows a superb cycling stability. Almost no capacitance decay was observed after 100, 000 cycles. Highlights: Corncob residue was used to prepare porous carbon for supercapacitor electrodes. Green and low-cost steam activation without pre-carbonization was used. The obtained porous carbon achieves high surface area and high yield after ash-removal. The porous carbon exhibits a high capacitance of 314 F g −1 in 6 M KOH electrolyte. No capacitance decay was observed after 100, 000 cycles for a symmetrical cell. Abstract: In this report, corncob residue, the main by-product in the furfural industry, is used as a precursor to prepare porous carbon by a simple and direct thermal treatment: one-step activation without pre-carbonization. As a consequence, the corncob residue derived porous carbon achieves a high surface area of 1210 m 2 g −1 after ash-removal. The carbon material has the advantages of low cost and low environmental impact, with a superior electrochemical performance compared to those polymer-based synthetic carbons as electrode material for a supercapacitor. The carbon electrode exhibits a high capacitance of 314 F g −1 in 6 M KOH electrolyte. The corresponding sample also shows a superb cycling stability. Almost no capacitance decay was observed after 100, 000 cycles. The excellent electrochemical performance is due to the combination of a high specific surface area with a fraction of mesopores and highly stable structure.