Improvement of Electrochemical Capacitance of Activated Carbon Electrodes from African Palm Shell Modified with HNO3

Autor:	Daniel Borrás, Sara Natalia Herrera Penagos, Erika Arenas, Zulamita Zapata
Rok vydání:	2021
Předmět:	Electrochemical capacitance Materials science Chemical engineering Electrode medicine Shell (structure) Activated carbon medicine.drug
Zdroj:	ECS Transactions. 100:27-35
ISSN:	1938-6737 1938-5862
DOI:	10.1149/10001.0027ecst
Popis:	Activated carbon electrodes were synthetized from African palm shell with KOH (CK) at 2/1 KOH/biomass mass ratio and treated thermically at 700°C (1056 m2/g). Then CK was modified at different conditions by surface treatment using HNO3/CK impregnation mass ratios 1 and 12, temperatures between 25 – 80°C, impregnation time 1 – 4 h. The performance of electrodes as supercapacitors was evaluated in 1 M H2SO4 using electrical impedance spectroscopy (EIS) and charge/discharge technique (CP). The results showed that the specific capacitance increases upon oxidation (57 F/g up to 89.7 F/g). The highest capacitance was obtained for sample prepared at impregnation ratio 1, 4 h and 25°C (606 m2/g) without increasing the equivalent resistance series significantly. These results were influenced mainly by the increased of nitrogen functional groups rather than specific surface area, which confirm that the surface composition has a high influence on the electrochemical performance.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::86ded4f5945f8e084dadd40ec66663c4 https://doi.org/10.1149/10001.0027ecst Zobrazit plný text záznamu