Tapas Kuila, Naresh Chandra Murmu and Joong Hee Lee
Accepted Abstracts: J Nanomed Nanotechnol
Surface functional groups play an important role in determining the specific capacitance behavior of graphene. In chemical synthesis, surface modified graphene was derived from graphene oxide (GO) modified with different modifying agents such as sulfonated poly-ether-ether ketone (SPEEK), sodium 4-aminoazobenzene-4'-sulfonate (SAS), its aryl diazonium salt (ADS) and sodium poly-styrene sulfonate (PSS). The surface modified GO was reduced using hydrazine monohydrate in aqueous media. Similarly, one-step electrochemical exfoliation of graphite was employed to obtain surface modified graphene. In comparison to chemical methods, electrochemical synthesis is cost-effective and devoid the use of toxic and hazardous chemicals. Moreover, the defect content in electrochemically obtained graphene was relatively lower than that of chemically derived graphene. The surface modifier used in the electrochemical exfoliation of graphite actively played an additional role as electrolyte during the electrolysis experiment. 9-anthralene carboxylic acid (9ACA), 6-amino-4-hydroxy-2-naphthalenesulfonic acid (ANS) and SPEEK were served the dual role as electrolyte and surface modifier. X-ray diffraction (XRD), Transmission electron microscopy (TEM), Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Fourier transform infrared spectroscopy (FT- IR), UV-Vis spectroscopy, etc. were used to analyze the structural and morphological features of synthesized graphene. Thermal stability was also determined by Thermogravimetric analysis (TGA). Electrochemical performances were evaluated by Cyclic voltammetry (CV), charge-discharge and electrochemical impedance spectroscopy analysis. The specific capacitance of different graphene varied from 250-476 F g -1 at low current density. The electrochemical stabilities of graphene were determined by 1000 charge-discharge cycles suggesting its utility as green energy storage electrode materials
Tapas Kuila is working as a DST Inspire Faculty at CSIR-Central Mechanical Engineering Research Institute, Durgapur since November-2012. He did his Postdoctoral Research in the Department of BIN Fusion Technology, Chonbuk National University since September, 2009. He received his Ph.D. in Chemistry from Indian Institute of Technology Kharagpur, India. Presently, he is working on the surface modification of chemically derived graphene and its application in supercapacitor devices. He has published more than 45 scientific articles in dif ferent peer-reviewed journal