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1.
J Colloid Interface Sci ; 512: 151-157, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29059548

RESUMO

In present work, for improving the electrochemical performance of conductive polymer, poly ortho aminophenol (POAP)/1-Butyl-3-methylimidazolium Chloride, [bmim]Cl composite films have been fabricated by POAP electropolymerization in the presence of [bmim]Cl as active electrodes for electrochemical supercapacitors. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. Analysis of DFT-B3LYP/6-31G∗ computational results, and AIM (atom-in-molecule) theory calculations, show that the atomic-scale electronic properties are generally depend on the bonding and electronic molecular structures (and thus their variation with the external bias in real nano-electrochemical circuits). The supercapacity behavior of the composite film was attributed to the (i) high active surface area of the composite, (ii) charge transfer along the polymer chain due to the conjugation form of the polymer and finally (iii) synergism effect between conductive polymer and [bmim]Cl.

2.
J Colloid Interface Sci ; 505: 1158-1164, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28715859

RESUMO

In present work, for improving the electrochemical performance of conductive polymer, POAP/3-methyl-1-[2-(2-{2-[2-[(3-methyl-1-H-imidazol-3-ium-1-yl)ethoxy]ethoxy}-ethoxy)ethyl]-1-H-imidazol-3-ium dichloride (MIEID) composite films have been fabricated by poly ortho aminophenol (POAP) electropolymerization in the presence of MIEID as active electrodes for electrochemical supercapacitors. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. Analysis of density functional theory (DFT) results show that the atomic-scale electronic properties are generally depend on the bonding and electronic molecular structures (and thus their variation with the external bias in real nano-electrochemical circuits). Composite film kept more than 90% percent of its capacitance after 1000 charging-discharging cycles, while the coulombic efficiency (η) is as high as 95%. Results suggesting composite film can be used as supercapacitor electrode material with excellent specific capacitance (487Fg-1) which indicates this material is a promising electrode material used in high power applications.

3.
J Colloid Interface Sci ; 503: 10-16, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28500935

RESUMO

In present work, for improving the electrochemical performance of conductive polymer, POAP/1-octadecyl-3-methylimidazolium Bromide ([OMD]Br) composite films have been fabricated by POAP electropolymerization in the presence of [OMD]Br as active electrodes for electrochemical supercapacitors. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. Analyses of DFT results show that the atomic-scale electronic properties are generally depend on the bonding and electronic molecular structures (and thus their variation with the external bias in real nano-electrochemical circuits). The supercapacity behavior of the composite film was attributed to the (i) high active surface area of the composite, (ii) charge transfer along the polymer chain due to the conjugation form of the polymer and finally (iii) synergism effect between conductive polymer and [OMD]Br.

4.
J Colloid Interface Sci ; 500: 315-320, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28412638

RESUMO

This study demonstrates a method for improving supercapacitive performance of electrochemically synthesized conductive polymer. In this regards, 1-Butyl-3-methyl imidazolium hexafluorophosphate (BI) as a new high efficient ionic liquid was synthesized using chemical approach and then fabricated POAP/BI films by electro-polymerization of POAP in the presence of BI to serve as the active electrode for electrochemical supercapacitor. Theoretical study (AIM) and electrochemical analysis have been used for characterization of ionic liquid and POAP/BI composite film. Different electrochemical methods including galvanostatic charge-discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. This work introduces new most efficient materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

5.
J Colloid Interface Sci ; 497: 258-265, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28285054

RESUMO

In this work, we synthesized amine functionalized graphene oxide (GOA), by using of 1-methyl, 3-butyl Imidazole ionic liquid, triphenylphosphine, 1,6-diamino hexane in DMSO medium. Afterward, dried GOA used for sulfonated graphene oxide (GOS). For improving electrochemical properties of the poly ortho aminophenol (POAP), we fabricated POAP/GOS films by electro-polymerization of POAP in the presence of GOS to serve as the active electrode for electrochemical supercapacitor. Different electrochemical methods including galvanostatic charge-discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. Finally, the local charge and energy transfer of the molecular system is calculated, using DFT/AIM theories. Results show that the oxygen and nitrogen atoms of phenyl (Ph)/(Ph-OH) rings and -Ph-CO-N-R-N-R″ -SO3H ended functional group, play domain role in intra-molecular charge and energy transfer. The major aim of this computational study method is to propose or effective design electro-chemical molecular systems having different atomic basins/functional groups response (sensitivities) to external voltage. This work introduces new most efficient materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

6.
J Colloid Interface Sci ; 490: 695-702, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27978454

RESUMO

Magnetic functional graphene oxide (MFGO) has been synthesized in this work using FeCl4- magnetic anion paired with 1-methyl imidazolium cation. Hybrid poly ortho aminophenol (POAP)/MFGO films have then been prepared via POAP electropolymerization in the presence of MFGO nanosheets, serving as active electrodes for electrochemical supercapacitors. The FeCl4- functional group in MFGO plays a major part in atomic scale charge/energy transfer and consequently intramolecular electrochemical phenomena in MFGO systems, as shown by the theoretical results. POAP/MFGO composite films have been characterized by surface and electrochemical analyses. The performance of the system has been investigated by various electrochemical methods such as galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy. Novel nanocomposite compounds have been developed in this work for electrochemical redox capacitors. The advantages of these compounds include simple synthesis method, high active surface area and stability in aqueous electrolytes.

7.
J Colloid Interface Sci ; 490: 444-451, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914344

RESUMO

Inhibition performance of Thymus vulgaris plant leaves extract (thyme) as environmentally friendly (green) inhibitor for the corrosion protection of stainless steel (SS) type 304 in 1.0molL-1 HCl solution was studied by potentiodynamic polarization, electrochemical impedance (EIS) and electrochemical noise measurements (EN) techniques. The EN data were analyzed with FFT technique to make the spectral power density plots. The calculations were performed by MATLAB 2014a software. Geometry optimization and calculation of the structural and electronic properties of the molecular system of inhibitor have been carried out using UB3LYP/6-311++G∗∗ level. Moreover, the results obtained from electrochemical noise analysis were compared with potentiodynamic polarization and electrochemical impedance spectroscopy. All of the used techniques showed positive effect of green inhibitor with increasing inhibitor concentration.


Assuntos
Extratos Vegetais/química , Aço Inoxidável/química , Thymus (Planta)/química , Corrosão , Espectroscopia Dielétrica , Química Verde , Modelos Moleculares
8.
J Colloid Interface Sci ; 490: 91-96, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27870964

RESUMO

In this paper firstly, 1-methyl-3-methylimidazolium bromide (MB) as a new high efficient ionic liquid was synthesized using chemical approach and then fabricated POAP/MB films by electro-polymerization of POAP in the presence of MB to serve as the active electrode for electrochemical supercapacitor. Theoretical study (AIM) and electrochemical analysis have been used for characterization of ionic liquid and POAP/MB composite film. Different electrochemical methods including galvanostatic charge-discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. This work introduces new most efficient materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

9.
J Colloid Interface Sci ; 478: 181-7, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27295320

RESUMO

An effective approach for increasing the life cycle of poly ortho aminophenol (POAP) as a p-type conductive polymers is combining conventional conductive polymers and nanomaterials to fabricate hybrid electrodes. In this paper, functionalized graphene oxide (FGO) has first been synthesized using a chemical approach. Hybrid POAP/FGO films have then been fabricated by POAP electropolymerization in the presence of FGO nanoparticles as active electrodes for electrochemical supercapacitors. Based on the atomic scale study results, it seems that H3PO4(-) oxygen atoms and terminal pyridine ring nitrogen atoms play a crucial role in the intramolecular charge and energy transfer in the FGO molecular systems. Theoretical studies, surface and electrochemical analyses have been used for characterization of POAP/FGO composite films. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. This work introduces new nanocomposite materials for electrochemical redox capacitors with such advantages as the ease of synthesis, high active surface area and stability in an aqueous electrolyte.

10.
J Colloid Interface Sci ; 473: 126-31, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27061364

RESUMO

Conductive polymers are usually used as an electrode in redox supercapacitor. However, due to accumulation of stress on polymer during repeating charge-discharge process, the cycle life of pure conductive polymer is poor, which needs to be further improved. For this purpose, combining conventional conductive polymers active material and nanomaterials to fabricate hybrid electrode has been considered to be one of the efficient avenues. In this paper, a simple and rapid electrochemical method has been carried out to prepare Eu2O3 nanoparticles and hybrid POAP/Eu2O3 to serve as the active electrode for electrochemical supercapacitor. Structural and morphological characterisations of Eu2O3 and composite film were carried out using powder X-ray diffraction, field emission scanning electron microscopy and energy dispersion of X-rays. Their electrochemical properties were also investigated using cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The as-prepared composites had excellent properties in the specific capacitance and a coulombic efficiency of 95%. The as-prepared composites had excellent properties in the capacitance, and its specific capacitance was up to 375Fg(-1) and a coulombic efficiency of 95%. This work introduces new nanocomposite materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

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