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    The chemical synthesis and characterizations of silver-doped polyaniline: role of silver-solvent interactions
    (SPRINGER, 2020) Tas, Recep; Can, Muzaffer; Sari, Hayati
    In this work, we successfully synthesized silver-doped polyaniline (NPANI-Ag-X; X represents I- and BF4- dopants,) by using chemical oxidation polymerization in various solvent media, which are deionized water, dimethylformamide, acetonitrile, 1,4-dioxane, tetrahydrofuran and acetone to give new features into polyaniline (PANI). Then, the solvent effects on the formation of NPANI-Ag-X were investigated. Most of the solvents used in the syntheses show ligand properties and form complexes with metal ions. According to their stability, these complexes can inhibit the reactions of metal ions. Polymer samples were characterized by using scanning electron microscopy, X-ray diffractions, energy-dispersive X-ray analysis, Fourier transform infrared spectrometry, atomic absorption spectrometer, ultraviolet-visible spectrophotometers, thermal analysis (TGA, DTA) and electrical conductivity measurements. The experimental results obtained show that some properties such as crystallinity, conductivity, metal contents and surface area of PANI polymers have changed with the addition of silver to the polymer. Studies have also shown that these properties can be controlled by the exchange of metal ions and solution media. It was observed that the solvents were effective in adding metal to the polymer and the amount of metal in the synthesized polymers varied depending on the solvent used.
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    Effects of solvent and copper-doping on polyaniline conducting polymer and its application as a counter electrode for efficient and cost-effective dye-sensitized solar cells
    (Elsevier Science Sa, 2016) Tas, Recep; Gulen, Mahir; Can, Muzaffer; Sonmezoglu, Savas
    In this study, the synthesis of Copper-doped polyaniline (NPANI-Cu-X) was performed in the following solvents: H2O, DMF, DO, THF, ACTN and ACN, and then the solvent effects on the formation of NPANI-Cu-X (X represents the dopants, I- and BF4-) were investigated. NPANI-Cu-X was characterized using scanning electron microscopy (SEM), X-ray diffractions (XRD), energy-dispersive X-ray analysis (EDAX), Fourier transform infrared spectrometry (FTIR), Atomic Absorption spectrometer (AAS), Ultraviolet-visible spectrophotometers (UV-vis), thermal analysis (TGA, DTA) and electrical conductivity measurements. The results show that the solvent is effective in the formation of NPANI-Cu-X. This effect was observed in the polymer structures, conductivities, copper contents and crystalline structures. The NPANI-Cu-X polymers synthesized with the various solvents were notably different from each other because some of the solvents create a copper-solvent complex with the copper. To understand the influence of solvent type and Cu inclusion on photoelectric performance, the obtained PANI were employed as counter electrode in a DSSC configuration. The highest double layer capacitance (24.1 mu F), low charge transfer resistance (5.13 Omega) together with series resistance (14.62 Omega), and good photovoltaic performance with conversion efficiency (6.37%) for counter electrodes are obtained the NPANI-Cu-X in ACN solvent media which is higher than that fabricated with N-PANI in same solvent media (1.36%). These results represent a promising route for developing new counter electrodes of Pt-free DSSCs by Cu doping and choosing an appropriate solvent. (C) 2015 Elsevier B.V. All rights reserved.
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    Exploring on Photovoltaic Performance of Dye-Sensitized Solar Cells Using Polyaniline as a Counter Electrode: Role of Aluminum-Solvent Interactions
    (Ieee-Inst Electrical Electronics Engineers Inc, 2017) Tas, Recep; Can, Muzaffer; Sonmezoglu, Savas
    In this work, we successfully synthesized aluminumdoped polyaniline in various solvent media using chemical oxidation polymerization, and for the first time, investigated their applications as counter electrode (CE) in dye-sensitized solar cells (DSSCs). The experimental results (field emission scanning electron microscopy/energy dispersive X-ray analysis, atomic absorption spectrometer, Fourier transform infrared spectroscopy, thermogravimetric/differential thermal analysis, etc.) showed that critical properties such as crystallinity, conductivity, and surface area of PAni polymers can be controlled through both Al ions and/or solvent media. The photovoltaic performance of DSSCs was evaluated by current density-voltage (J-V) and external quantum efficiency measurements. The differences in the conversion efficiencies (eta) were explained based on the electrocatalytic abilities and electron transfer properties of CEs. Of the CEs in various solvents, the P@6 CE in acetone showed the best electrocatalytic ability and highest eta of 5.97%. This is even higher than that of the cell with Pt CE (5.75%). Furthermore, its stability under a prolonged irradiation is somewhat lower or close to the Pt CE, P@ 6 CE based DSSC showed the characteristics of rapid activity onset, high multiple start/stop capability, and superior irradiation stability. This novel concept-along with promising electrocatalytic activity and facile electron transfer-provides a new approach to enhance the photovoltaic performances of Pt-free DSSCs.
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    Increasing Photocatalytic Stability and Photocatalytic Property of Polyaniline Conductive Polymer
    (Springer Int Publ Ag, 2020) Dogan, Deniz; Tas, Recep; Can, Muzaffer
    This study aims to enhance the photocatalytic properties and stability of polyaniline (PANI) by preparing polyaniline-metal oxide composites. Polyaniline and polyaniline-metal oxide composites were synthesized via chemical polymerization method and characterized by using scanning electron microscopy, X-ray diffraction (XRD), energy-dispersive X-ray analysis, and Fourier transform infrared spectrometry. The morphological characteristics of the polymers synthesized in media with and without metal oxide are quite different from each other. These differences are due to the presence of metal oxides in the polymer structure, and the interactions between PANI-metal oxides, as mentioned in the XRD interpretations. The photocatalytic properties of polyaniline and each polyaniline-metal oxide composite were investigated using methylene blue (MB) under UV light and in the dark. (MB is one of the pollutant dyes found in wastewater.) The findings showed that photocatalytic property and stability of polyaniline can be enhanced by preparing the polyaniline-metal oxide composites. TheE(g)values of the selected metal oxides are around 3 eV values. The metal oxides, having the 3 eV energy bandgap range, exhibit better photocatalytic properties. [GRAPHICS] .
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    Increasing Photocatalytic Stability and Photocatalytic Property of Polyaniline Conductive Polymer
    (SPRINGER INTERNATIONAL PUBLISHING AG, 2020) Dogan, Deniz; Tas, Recep; Can, Muzaffer
    This study aims to enhance the photocatalytic properties and stability of polyaniline (PANI) by preparing polyaniline-metal oxide composites. Polyaniline and polyaniline-metal oxide composites were synthesized via chemical polymerization method and characterized by using scanning electron microscopy, X-ray diffraction (XRD), energy-dispersive X-ray analysis, and Fourier transform infrared spectrometry. The morphological characteristics of the polymers synthesized in media with and without metal oxide are quite different from each other. These differences are due to the presence of metal oxides in the polymer structure, and the interactions between PANI-metal oxides, as mentioned in the XRD interpretations. The photocatalytic properties of polyaniline and each polyaniline-metal oxide composite were investigated using methylene blue (MB) under UV light and in the dark. (MB is one of the pollutant dyes found in wastewater.) The findings showed that photocatalytic property and stability of polyaniline can be enhanced by preparing the polyaniline-metal oxide composites. TheE(g)values of the selected metal oxides are around 3 eV values. The metal oxides, having the 3 eV energy bandgap range, exhibit better photocatalytic properties. Graphic It was aimed to investigate the photocatalytic properties and to increase the photocatalytic properties of polyaniline with the metal oxide. Polyaniline-metal oxide composites were synthesized and characterized. And their photocatalytic properties of each oxide composite were investigated by degradation of methylene blue under UV light and in dark media.
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    Increasing the crystallite and conductivity of polypyrrole with dopant used
    (Springer Heidelberg, 2014) Tohumcu, Canan; Tas, Recep; Can, Muzaffer
    The chemical polymerization method is very convenient for obtaining a plurality of the polymer. Chemical synthesizes of polypyrrole (PPy) were performed in acetonitrile solutions containing different dopants: dodecylbenzene sulphonic acid (DBSA), tetrafluoroborate (BF4 (-)), perchlorate (ClO4 (-)) and oxalate (C2O4 (2-)). These polymers were characterized by using scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis) spectrophotometer, Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD) techniques and dry conducting measurement. It was observed that the interactions between the polymers and dopant materials are completely different from each other. As a result of this interaction, the conductivities and crystal structures of PPy are also different from each other. Results in this work showed that the dopants used affected both electrical conductivities and crystal structures of PPy.
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    Photocatalytic activity of polyaniline and neutral polyaniline for degradation of methylene blue and malachite green dyes under UV Light
    (Springer, 2021) Haspulat Taymaz, Bircan; Tas, Recep; Kamis, Handan; Can, Muzaffer
    A polyaniline (PANI) and neutral Polyaniline (NPANI) have been synthesized in acetonitrile-water mixture via the chemical oxidative polymerization of aniline. Scanning electron microscopy, FTIR spectra, UV-vis spectroscopy measurements were used to characterize the resulting PANI and NPANI. The photocatalytic activities of PANI and NPANI were investigated by the degradation of methylene blue (MB) and malachite green (MG) dyes in aqueous medium under UV light irradiation. MB and MG dyes completely degraded under UV light irradiation in the presence of NPANI after 60 and 75 min, respectively. The effect of dye type, irradiation time, dye concentration and photocatalyst amount on photocatalytic performance of PANI and NPANI have been examined under UV light irradiation. Three kinetic models have proposed for photocatalytic degradation of dyes by using PANI and NPANI under UV light illumination. This work explores the easy way to synthesize efficient PANI and NPANI polymers to degrade organic compound under both UV and visible light irradiations.
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    Polyaniline micro-rods based heterojunction solar cell: Structural and photovoltaic properties
    (Amer Inst Physics, 2012) Sonmezoglu, Savas; Tas, Recep; Akin, Seckin; Can, Muzaffer
    The present paper reports the fabrication and photovoltaic characterization of pure and dodecyl benzene sulfonic acid (DBSA)-doped polyaniline (PAni) micro-rods polymer/n-Si heterojunction solar cells, and also the morphological and structural properties of pure and micro-rods PAni doping with DBSA. The device shows a strong photovoltaic behavior with a maximum open-circuit voltage V-oc of 0.83 V, a short-circuit current J(sc) of 14.72 mA cm(-2), fill factor FF of 0.54 resulting in an estimated device efficiency eta of 6.13% under simulated solar light with the intensity of 100 mW/cm(2). The results indicate that the Au/DBSA-doped PAni micro-rods/n-Si heterojunction structure might be promising for the solar cell applications. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4772019]
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    Preparation and characterization of polyaniline microrods synthesized by using dodecylbenzene sulfonic acid and periodic acid
    (Scientific Technical Research Council Turkey-Tubitak, 2015) Tas, Recep; Can, Muzaffer; Sonmezoglu, Savas
    The preparation of polyaniline (PANI) microrod arrays in the presence of dodecylbenzene sulfonic acid (DBSAH), a structure-directing agent, and in the presence of periodic acid (H5IO6), an oxidant in aqua-acidic media, was investigated. DBSAH was performed to distinguish the roles of both surfactant and dopant. The method of preparation of DBSAH and H5IO6 doped PANI (DBSAH-PANI) microrods in a reversed micelle had previously not been reported. The characterizations of the PANI microrods were determined by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, (EDX) and X-ray diffraction (XRD). Based on the SEM results, we found that PANI microrods occur in the presence of DBSAH in the polymerization medium, while the XRD results showed that PANI-DBSA gave clearer crystallinity than PANI. At room temperature, the DC conductivities of pure PANI and PANI-DBSA were 9.5 x 10(-2) S/cm and 9.2 x 10(-2) S/cm(-4) x 10(-2) S/cm, respectively, based on the molar ratio of DBSA. The experimental results suggested that it is possible to control both the electrical conductivities and the crystal structures of PANI microrods with DBSAH dopants' incorporation level.