TAILIEUCHUNG - Tra Bac activated carbon used as electrode material in aqueous supercapacitor
In our best results, a specific capacitance of 20 F/g was obtained at the charge–discharge current of 1 A/g. Even at very high applied current range, the capacitance dropped slowly, less than fifteen percent. | Journal of Science and Technology 55 (1B) (2017) 257–265 TRA BAC ACTIVATED CARBON USED AS ELECTRODE MATERIAL IN AQUEOUS SUPERCAPACITOR Van Man Tran1, *, Dinh Tan Phat Pham1, Huu Tru Nguyen2, Van Hoang Nguyen1, My Loan Phung Le1, 2 1 Faculty of Chemistry, HCMUS–VNUHCM 227 Nguyen Van Cu Street, Ward 4, District 5, Ho Chi Minh City, Vietnam 2 Applied Physical Chemistry Laboratory, HCMUS–VNUHCM 227 Nguyen Van Cu Street, Ward 4, District 5, Ho Chi Minh City, Vietnam * Email: tvman@ Received: 30 December 2016; Accepted for publication: 9 March 2017 ABSTRACT Carbon materials . activated carbon, carbon aerogel, carbon nanotubes (CNTs) store a high electric power and a great stable cyclability when they are used as electrode materials in electrical double–layers capacitor (EDLC). In this work, activated carbon from coconut shells which was cooperatively provided by the Tra Bac Joint Stock Corporation–TRABACO was investigated as electrode materials in EDLC. Raw carbon material with large particle size was crushed and sieved to obtain a 43 µm grain size fraction for electrochemical characterization. The symmetric EDLC configuration based on Tra Bac carbon was tested in Swagelok–type cell using KOH electrolyte in the potential range 0–1 V. The CV curves indicated that charges can be stored enormously with a high reversibility and stability. The high performance of EDLC based carbon in KOH electrolyte could be further improved by variation of electrode composition. The rate capability of the material was also studied under different current ranges. In our best results, a specific capacitance of 20 F/g was obtained at the charge–discharge current of 1 A/g. Even at very high applied current range, the capacitance dropped slowly, less than fifteen percent. Keywords: activated carbon, aqueous supercapacitors, cyclic voltammetry. 1. INTRODUCTION Energy storage in batteries and capacitors is reliable for number of portable to large scale applications. The high .
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