Activated carbon derived from rice husk by NaOH activation and its application in supercapacitor

The aim of the work "Activated carbon derived from rice husk by NaOH activation and its application in supercapacitor" is to prepare a low-cost, high specific surface area activated carbon with microporous and mesoporous ranges using rice husk as the raw material. The effects of activation temperature on the specific surface area, pore structure, morphology and thermal stability of the AC samples have been examined. The AC samples were proved to be excellent electrode material for supercapacitor, hence solve the disposal and pollution problems of rice husk.
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Activated carbon derived from rice husk by NaOH activation and its application in supercapacitorThis article appeared in a journal published by Elsevier. The attachedcopy is furnished to the author for internal non-commercial researchand education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier’s archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/authorsrights Authors personal copy Available online at www.sciencedirect.com Progress in Natural Science Materials International Progress in Natural Science: Materials International 24 (2014) 191–198 www.elsevier.com/locate/pnsmi www.sciencedirect.comOriginal Research Activated carbon derived from rice husk by NaOH activation and its application in supercapacitor Khu Le Vann, Thu Thuy Luong Thi Physical Chemistry Department, Hanoi University of Education, Hanoi 1000, Vietnam Received 21 October 2013; accepted 13 May 2014 Available online 10 June 2014Abstract Four activated carbon (AC) samples prepared from rice husk under different activation temperatures have been characterized by N2 adsorption–desorption isotherms, thermogravimetric analysis (TGA–DTA), Fourier transform infrared spectroscopy (FTIR) and scanning electronmicroscopy (SEM). The specific surface area of AC sample reached 2681 m2 g 1 under activation temperature of 800 1C. The AC sampleswere then tested as electrode material; the specific capacitance of the as-prepared activated carbon electrode was found to be 172.3 F g 1 usingcyclic voltammetry at a scan rate of 5 mV s 1 and 198.4 F g 1 at current density 1000 mA g 1 in the charge/discharge mode.& 2014 Chinese Materials Research Society. Production and hosting by Elsevier B.V. All rights reserved.Keywords: Rice husk; Activated carbon; Supercapacitor; Surface area; Micropore1. Introduction life. On the basis of the charge storage mechanism, super- capacitors are basically classified into three categories: electric Vietnam became the worlds top rice exporter and exported double layer capacitors (electrostatic charge accumulation at5.949 million tons of rice in the year 2012. Normally, rice husk the electrode–electrolyte interface), pseudocapacitors (fast andis treated as waste and disposed at power plant sites, and leads reversible redox processes at the electroactive material surface)to a serious environmental problem. Therefore, it is important and hybrid capacitors (the electric double layer capacitanceto make full use of the husk. Recently, rice husk is used as and the pseudocapacitance) [8]. In the case of AC, the energyprecursors to produce activated carbon (AC) [1], zeolite [2,3], is stored in the electric double layer, which occurred at thesilica [4,5], concrete [6], etc. With porous structure, high porous carbon electrode/electrolyte interface [9]. In order tosurface area and low cost, AC has attracted considerable obtain a reasonable energy density, activated carbon must haveattention and has been widely used as catalyst carriers (catalytic high specific surface area to ensure high specific capacitancesupport), adsorbent to adsorb m ...