Polyaniline-sulfate Salt Research Articles

Hybrid material of polyaniline incorporated industrial waste of fly ash to enhance the electrode performance of polyaniline in supercapacitor application

The existing high market potential for supercapacitors in electric vehicles created enthusiasm for the development of safer and high-performance supercapacitor gadgets. The ongoing examination endeavors on electrochemical power sources are composed toward achieving high-explicit energy, high-explicit power, long-cycle life, and so forth, at a realistic cost. In this work, low-cost hybrid material of polyaniline-sulfate salt and ash from the bituminous coal is synthesized via in situ polymerization of aniline. The formation of hybrid in this polymerization process was confirmed from FTIR, XRD, EDAX, and TGA. Thus, prepared polyaniline-sulfate●ash (PANI-ash) hybrid is taken as electro-active material for the construction of supercapacitor cell in a symmetric configuration in 1 M H2SO4 electrolyte. PANI-ash, wherein ash prepared at 600 oC of bituminous coal, gave higher electrochemical performance compared to its individual components of PANI and ash materials. Initial specific capacitance observed for the samples of PANI, PANI-A400, and PANI-A600 are 155, 328, and 363 F g−1, respectively. PANI-A600 symmetric cell system subjected to a higher current density of 0.75 A g−1 for 10,000 cycles. Remaining in specific capacitance values of polyaniline salts at 10,000 CD cycles is found to be 70 %, and further at 35,000 cycles, it shows 43% retention of specific capacitance.

Methyl triphenylphosphonium permanganate as a novel oxidant for aniline to polyaniline-manganese(II, IV) oxide: material for high performance pseudocapacitor

In this work, organic-inorganic composite materials of polyaniline and manganese oxide were synthesized and investigated their electrochemical performance. This composite material was prepared by oxidizing aniline with methyl triphenylphosphonium permanganate as a novel organic oxidant via aqueous, emulsion, and interfacial polymerization pathways. This process led to the formation of polyaniline-sulfate salt (PANI-SA-Mn5O8). Formation of polyaniline-sulfate salt was confirmed from FT-IR, EDAX, and XRD results. Formation of Mn5O8 was supported by XRD spectrum. PANI-SA-Mn5O8 prepared via emulsion polymerization pathway was obtained in porous nanorod morphology with high conductivity (9.4 S cm−1) compared to that of the other sample prepared via interfacial pathway (1.7 S cm−1). Whereas, aqueous polymerization pathway resulted in sheet-like morphology with a conductivity of 0.8 S cm−1. These composites were used as pseudocapacitive electrode materials. Electrochemical characterization (cyclic voltammetry, charge-discharge, and electrochemical impedance measurement) showed that composite prepared via emulsion polymerization pathway gave better electrochemical performance, and showed good cycling behavior.

One-step preparation of sulfonated carbon and subsequent preparation of hybrid material with polyaniline salt: a promising supercapacitor electrode material

The present trend to increase the energy density of electrochemical supercapacitor is to hybrid the electrochemical double layer capacitance electrode materials of carbon with loading or encapsulation of transition metal oxide or conductive polymeric pseudocapacitor materials as the binary or ternary hybrid electrochemical active materials. In this work, we selected polyaniline salt-sulfonated carbon hybrid (PANI-SA•C SA ) as a cheaper electrode material for supercapacitor electrode. Sulfonated carbon (C SA ) was prepared from hydrothermal carbonization of furaldehyde and p-toluenesulfonic acid. Polyaniline-sulfate salt containing sulfonated carbon was prepared by chemical oxidative polymerization of aniline using ammonium persulfate in presence of sulfuric acid and sulfonated carbon via aqueous, emulsion and interfacial polymerization pathways. Formation of hybrid material was confirmed from scanning electron microscopy. Among the hybrid prepared with three different polymerization pathways, hybrid prepared by aqueous polymerization pathway showed better electrochemical performance. The specific capacitance of the hybrid prepared via aqueous polymerization was 600 F g−1, which is higher than that of the pristine PANI-SA (350 F g−1) and C SA (30 F g−1). Hybrid material was subjected for 8000 charge-discharge cycles and at 8000 cycles; it showed 88% retention of its original specific capacitance value of 485 F g−1 with coulombic efficiency (97–100%). These results showed that C SA micro spheres prevent the degradation of PANI-SA chains during charge/discharge cycles. Specific capacitance, cycle life, low solution resistance, low charge transfer resistance and high phase angle value of PANI-SA•C SA supercapacitor cell indicates a higher performance supercapacitor system.

High‐temperature oxidation of aniline to highly ordered polyaniline–sulfate salt with a nanofiber morphology and its use as electrode materials in symmetric supercapacitors

AbstractIn this study, for the first time, aniline was oxidized by ammonium persulfate (APS) at higher temperatures without any protic acid, and APS acted as an oxidizing agent and a protonating agent. During the oxidation of aniline by APS, sulfuric acid formation occurred, and the sulfuric acid was incorporated into polyaniline (PANI) as a dopant. PANI–sulfate samples were characterized by IR spectroscopy, X‐ray diffraction, and scanning electron microscopy techniques. In this methodology, a highly ordered PANI–sulfate salt (H2SO4) with a nanofiber morphology was synthesized. Interestingly, a PANI base was also obtained with a highly ordered structure with an agglomerated netlike nanofiber morphology. PANI–H2SO4 was used as an electrode material in a symmetric supercapacitor cell. Electrochemical characterization, including cyclic voltammetry (CV), charge–discharge (CD), and impedance analysis, was carried out on the supercapacitor cells. In this study, the maximum specific capacitance obtained was found to be 273 F/g at 1 mV/s. Scan rate from cyclic voltammetry and 103 F/g at 1 mA discharge current from CD measurement. Impedance measurement was carried out at 0.6 V, and it showed a specific capacitance of 73.2 F/g. The value of the specific capacitance and energy and power densities for the PANI–H2SO4 system were calculated from CD studies at a 5‐mA discharge rate and were found to be 43 F/g, 9.3 W h/kg, and 500 W/kg, respectively, with 98–100% coulombic efficiency. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Polyaniline-supported acid as an efficient and reusable catalyst for a one-pot synthesis of β-acetamido ketones via a four-component condensation reaction

Polyaniline-supported acid salts such as polyaniline-hydrochloride, polyaniline-sulfate and polyaniline-nitrate were prepared by oxidation of aniline using ammonium persulfate as oxidizing agents. Polyaniline salts were used as catalyst for the preparation of β-acetamido ketones. Polyaniline-sulfate salt was found to be the best catalyst for the preparation of β-acetamido ketones. Present methodology offers several advantages, such as cheaper process, easy synthesis of stable catalyst, simple work-up procedure, and excellent activity with less amount of catalyst and in addition, the catalyst can be easily recovered after completion of the reaction and reusable without affecting its activity.

Green Approach for the Synthesis of Quinoxaline Derivatives in Water Medium Using Reusable Polyaniline-sulfate Salt Catalyst and Sodium Laurylsulfate

Quinoxaline derivatives have been prepared in excellent yields using very low amount of reusable polyaniline catalyst or polyaniline and sodium laurylsulfate from various 1,2-dicarbonyls and 1,2-diamines in aqueous medium. This methodology is being reported for the first time. The advantages of the polyaniline based sold acid catalyst are easy synthesis, stability, easy handling, convenient work up procedure and reusability of the catalyst.

Efficient, convenient and reusable polyaniline-sulfate salt catalyst for the synthesis of quinoxaline derivatives

Biologically important quinoxaline derivatives were prepared in excellent yields using very low amount of reusable polyaniline-sulfate salt catalyst from various 1,2-dicarbonyls and aromatic 1,2-diamines. This methodology is also very much useful for the synthesis of new quinoxaline derivative using sterically hindered diamine.

Polyaniline-sulfate salt as an efficient and reusable catalyst for the synthesis of 1,5-benzodiazepines and 2-phenyl benzimidazoles

Polyaniline-sulfate salt was used as an efficient catalyst for the preparation of benzodiazepines and 2-phenyl benzimidazoles in excellent yields. This method is applicable for the reaction of phenylenediamine with cyclic or acyclic ketones or aromatic aldehydes. The salient features of the present methodology are cheaper process, easy synthesis of stable catalyst, versatility and in addition, the catalyst can be easily recovered after completion of the reaction and reusable without affecting its activity.

Polyaniline‐Supported Sulfuric Acid Salt as a Powerful Catalyst for the Protection and Deprotection of Carbonyl Compounds.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Polyaniline-Supported Sulfuric Acid Salt as a Powerful Catalyst for the Protection and Deprotection of Carbonyl Compounds

Structurally different carbonyl compounds were converted into their corresponding cyclic acetals using polyaniline-sulfate salt as catalyst in dry toluene in excellent yield. In turn, useful deacetalization in aqueous medium was demonstrated. Chemoselective protection of carbonyl compounds was also demonstrated. The advantages of the polyaniline-sulfate salt are ease of preparation and handling, stability, reusability and activity.

Emulsion polymerization pathway for preparation of organically soluble polyaniline sulfate

In this work, aniline was polymerized directly to polyaniline sulfate salt without using protic acid. Polyaniline sulfate salt was prepared by an emulsion polymerization pathway using surfactants such as anionic surfactant (sodium lauryl sulfate), cationic surfactant (cetyltrimethylammonium bromide) and non-ionic surfactant (polyethylene glycol octadecyl ether). Anionic/cationic surfactants yield polyaniline sulfate salt in organic phase and non-ionic surfactant yields polyaniline sulfate in powder form. The dopant, i.e. sulfate ion, in polyaniline sulfate salt was generated from ammonium persulfate which was used to oxidize aniline. Ammonium persulfate acts both as an oxidizing agent and as a doping agent in the polymerization process of aniline to polyaniline sulfate salt. The spectral and electrical properties of the polyaniline salt synthesized by the emulsion polymerization pathway are compared with those of the polyaniline salt prepared by an aqueous polymerization pathway using sulfuric acid as protic acid.

Preparation of polyaniline-sulfate salt ­by emulsion and aqueous ­polymerization pathway without using ­protonic acid

Aniline was polymerized directly into polyaniline-sulfate salt without using protonic acid in this work. Polyaniline-sulfate salt was prepared by emulsion and aqueous polymerization pathways. The dopant i.e. sulfate ion in polyaniline-sulfate salt was generated from ammonium persulfate which was used for oxidizing aniline. Ammonium persulfate acts both as oxidizing agent as well as protonating agent in the polymerization process of aniline to polyaniline salt. The efficiency of oxidizing and protonating power of ammonium persulfate is increased by the use of surfactant. The activity of ammonium persulfate is further increased by the use of sulfuric acid as protonic acid. It may be necessary to consider the effect of sulfate ion which is generated during the oxidation process of aniline in the chemical polymerization of aniline to polyaniline salt by ammonium persulfate either aqueous or emulsion polymerization pathway in the presence of protonic acid/functionalized protonic acid. Copyright © 2001 John Wiley & Sons, Ltd.

The effect of zeolite on the curing of epoxy resin by polyaniline: a kinetic study

Polyaniline sulfate-zeolite composite was prepared by emulsion polymerization. Epoxy resin was cured using polyaniline-sulfate salt and various amounts of polyaniline sulfate-zeolite composite. The kinetics of the cure reaction for an epoxy resin based on the diglycidyl ether of bisphenol A (DGEBA) with polyaniline-sulfate and polyaniline sulfate-zeolite composite have been studied using differential scanning calorimetry (DSC) under isothermal and dynamic conditions. Isothermal kinetics analysis was performed using the phenomenological model of Kamal. Dynamic kinetic analysis was performed using Kissinger's method. Copyright © 2002 John Wiley & Sons, Ltd.

Preparation of polyaniline‐sulfate salt ­by emulsion and aqueous ­polymerization pathway without using ­protonic acid

AbstractAniline was polymerized directly into polyaniline‐sulfate salt without using protonic acid in this work. Polyaniline‐sulfate salt was prepared by emulsion and aqueous polymerization pathways. The dopant i.e. sulfate ion in polyaniline‐sulfate salt was generated from ammonium persulfate which was used for oxidizing aniline. Ammonium persulfate acts both as oxidizing agent as well as protonating agent in the polymerization process of aniline to polyaniline salt. The efficiency of oxidizing and protonating power of ammonium persulfate is increased by the use of surfactant. The activity of ammonium persulfate is further increased by the use of sulfuric acid as protonic acid. It may be necessary to consider the effect of sulfate ion which is generated during the oxidation process of aniline in the chemical polymerization of aniline to polyaniline salt by ammonium persulfate either aqueous or emulsion polymerization pathway in the presence of protonic acid/functionalized protonic acid. Copyright © 2001 John Wiley & Sons, Ltd.