Mahima Khandelwal; Anil Kumar
Abstract
N-doped graphene has been synthesized by the reduction of graphene oxide (GO) using 2-aminoisobutyric acid (AIB) as a reducing agent (N-GrAIB) under mild experimental conditions in aqueous medium. The reduction of GO was indicated by a change in its optical absorption as well as by its Raman spectrum ...
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N-doped graphene has been synthesized by the reduction of graphene oxide (GO) using 2-aminoisobutyric acid (AIB) as a reducing agent (N-GrAIB) under mild experimental conditions in aqueous medium. The reduction of GO was indicated by a change in its optical absorption as well as by its Raman spectrum and 13C solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR) studies. The latter two techniques also confirmed the doping of N. N-GrAIB exhibited fairly high conductivity (6.3 S/cm), high specific capacitance (228 F/g at 1 A/g) with good cycling stability for 1000 charge-discharge cycles, high coulombic efficiency (100-101%) and high energy density of 20.26 Wh/kg at a power density of 400 W/kg. The present work shows that this environmental benign N-doped graphene (N-GrAIB) could be a promising electrode material for supercapacitor applications. Copyright © 2016 VBRI Press
Mahima Khandelwal; Anil Kumar; Richa Baronia; Shraddha Tiwari; Avanish K. Srivastava; Surinder P. Singh; Sunil K. Singhal
Abstract
In the present work we report a facile method for the synthesis of Pt nanoparticles supported reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNTs) nanocomposite by an in-situ chemical reduction. The incorporation of MWCNTs to rGO leads to decrease in agglomeration between rGO sheets ...
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In the present work we report a facile method for the synthesis of Pt nanoparticles supported reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNTs) nanocomposite by an in-situ chemical reduction. The incorporation of MWCNTs to rGO leads to decrease in agglomeration between rGO sheets due to π – π interactions and higher loading of Pt nanoparticles. In this process, a mixture of exfoliated graphene oxide, CNTs and chloroplatinic acid was treated with a mixture of hydrazine hydrate and ammonium hydroxide at 95° C in an oil bath for 1 h. Pt nanoparticles of 4-6 nm size were homogeneously dispersed on rGO-CNTs nanocomposite as revealed by TEM analysis. Cyclic voltammetry measurements depict an anodic current density of 11.74 mA/cm2 that could be obtained using Pt/rGO-CNTs catalyst and 6.2 mA/cm2 using Pt/rGO catalyst during methanol oxidation, indicating that the catalytic activity of Pt/rGO-CNTs catalyst is almost 2 times higher than that of Pt/rGO catalyst. The electrochemical stability of Pt/rGO-CNTs catalyst was also found to be much higher as compared with that of Pt/rGO catalyst. Thus, Pt/rGO-CNTs catalyst has the potential to be used in the preparation of a promising anode material for direct methanol fuel cell. Copyright © 2016 VBRI Press