Hamidreza Zare-mehrjardi
Abstract
In this study, the surface of the glassy carbon electrode (GCE) is modified with the nanocomposite of graphene oxide (GO)/ ionic liquid (1-Butyl-3-methylimidazolium tetrafluoroborate; [BMIM]BF4). The electrochemical behavior of ascorbic acid (AA) and dopamine (DA) at the surface of the modified glassy ...
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In this study, the surface of the glassy carbon electrode (GCE) is modified with the nanocomposite of graphene oxide (GO)/ ionic liquid (1-Butyl-3-methylimidazolium tetrafluoroborate; [BMIM]BF4). The electrochemical behavior of ascorbic acid (AA) and dopamine (DA) at the surface of the modified glassy carbon electrode was studied using the differential pulse and cyclic voltammetric methods (DPV and CV). The results show good response sensitivity to AA and DA. The acceleration of the electron transfer rate and enhancement of the electroactive surface area is obtained due to a synergistic effect in the concurrent presence of GO and [BMIM]BF4 at the surface of the electrode. The presence of GO caused to a higher specific surface of the electrode, and ionic liquid ([BMIM]BF4) increased the ion conductivity and dispersibility in the modifier layer at the surface of the GCE. These results obtained in optimum conditions, show good peak separation for AA and DA (more than 300 mV), and the sub-micromolar detection limits for them. The obtained results in this work, make the modified GCE very effective in the manufacture of simple devices for the detection of AA and DA in human urine samples.
Soghra Fathalipour; Sima Pourbeyram; Sanaz Lotfi; Rasul Bulgar
Abstract
Silver nanoparticles (Ag NPs)-reduced graphene oxide was prepared through the in situ nucleation of Ag NPs on reduced, modified GO (rMGO). Glycine was used as a green reducing as well as modifier agent for GO to obtain rMGO. Nucleation of Ag NPs on rMGO was carried out at 80 ◦C at aqueous media. UV-Vis, ...
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Silver nanoparticles (Ag NPs)-reduced graphene oxide was prepared through the in situ nucleation of Ag NPs on reduced, modified GO (rMGO). Glycine was used as a green reducing as well as modifier agent for GO to obtain rMGO. Nucleation of Ag NPs on rMGO was carried out at 80 ◦C at aqueous media. UV-Vis, FT-IR, and XRD techniques confirmed the reduction, modification, and synthesis of Ag NPs. Meanwhile, the morphology of rMGO and rMGO-Ag nanocomposite was investigated with SEM and TEM images. The synthesized nanocomposite showed excellent catalytic behavior for the reduction of 4-nitrophenol (4-NP) by NaBH4. The electrocatalytic behavior of Ag NPs on rMGO for electroreduction of H2O2 was investigated by cyclic voltammetry (CV). In the optimum condition, H2O2 was determined with a detection limit of 9.4 µM and sensitivity of 0.52 µAµM-1. In addition, with the investigation of MIC data of nanocomposite, it was distinguished that this compound has excellent antibacterial activity.
Bakhtiar Khodavirdilo; Naser Samadi; Marzieh Ahari Salmasi
Abstract
In this study a new method by using graphene oxide (GO) Nano sheets-melamine composites and derivation of Poly (Styrene –alternative- Maleic Anhydride) (SMA), (SMA+Melamine) (SMA-M) were presented as Sorbents for the elimination of Lead ions from aqueous solutions. The adsorbents have the sufficiency ...
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In this study a new method by using graphene oxide (GO) Nano sheets-melamine composites and derivation of Poly (Styrene –alternative- Maleic Anhydride) (SMA), (SMA+Melamine) (SMA-M) were presented as Sorbents for the elimination of Lead ions from aqueous solutions. The adsorbents have the sufficiency to adsorb the Lead ions. Through the immobilization of melamine onto GO Nano sheets, the desired composite was synthesized and identified by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy and absorption atomic spectroscopy (AAS) techniques. The various experimental parameters such as pH and concentration of the aqueous solution of Lead (II) ion, the content of the Lead (II) ion the grapheme oxide-Melamine and SMA-M have been optimized. It was shown that the uptake efficiency of Lead (II) ion considerably increased after immobilization of Melamine on the GO Nano sheets and SMA.
