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Clay mineral obtained from Tuticorin in Tamilnadu, India (Indian Clay- IC) was purified and used to synthesise polyaniline-Indian clay nanocomposites (Pani-IC NCP) by polymerising aniline with the clay by chemical oxidation method using potassium perdisulphate as oxidant and by varying the aniline to clay ratio. The formation of composite in nanoscale was confirmed by XRD and TEM analysis. The in situ intercalative polymerization of monomer within the clays was ascertained by FTIR, UV–visible, XRD, SEM and TEM studies. The analyses of UV visible and FTIR spectroscopy demonstrated that aniline has been polymerized to Pani in its conducting emeraldine form. The conformation adopted by Pani Chains in the clay interlayer depended on the molar ratio of aniline to clay. SEM analysis showed the variation in morphology from granular agglomerate to layered flaky structure as the clay concentration was increased. Thermal stability of the nanocomposites was studied using TGA/DTA and DSC studies and it was found that they showed better thermal stability than their pristine polymers indicating the enhanced barrier property of the nanoclay. XRD showed that the clay host used accommodates higher amount of emeraldine salt than MMT. The Cyclic voltammetry studies of the synthesized nanocomposites showed the one with 0.5 g clay showed better electrochemical response. It exhibited good adherent behaviour on electrode surface at pH 1.0 with two oxidation peaks at 463 and 672 mV and two reduction peaks at 360 and 126 mV. By varying the atmosphere it was found that the nanocomposite modified electrode exhibited oxygen reducing capacity than their Bentonite counterpart. Chronoamperometric and Chronocoulometric studies were also carried out at inert as well as oxidising atmosphere which confirmed the above fact. EIS studies of the modified electrodes showed double layer capacitance value of 5.95 × 10−8 Fcm−2 with the bode phase angle of 70°.

Co-polymer of poly (3-methylthiophene -co- 3, 4-ethylenedioxythiophene) (PMT-co-EDOT) can be synthesized by electrochemical method using the basic monomers such as acetonitrile/tertiary butyl ammonium perchlorate medium. The electrosynthesized co-polymer was characterized like FT-IR, UV–visible, XRD, SEM-EDS analysis and AFM technique. The spectroelectro electrochromic properties of the co-polymer were characterized through UV-transmittance spectra coupled with cyclic voltammetry (CV). From the spectro electrochemical measurement, the coloration efficiency was 685 cm2/C and the optical contrast (Δ%T) was 84 at the wavelength of 420 nm were calculated. The polymer films were displayed multicolour electrochromism. This co-polymer system is applicable as electrochromic devices.

Poly (o-toluidine) (PoT) was synthesised by chemical polymerization method using ammonium persulphate as oxidizing agent. The para disubstituted aromatic rings band at 813 cm−1, indicating the polymer formation was confirmed by Fourier transform infrared spectroscopy (FTIR). The characterization of the polymer amorphous crystalline form was carried out using X-ray diffraction method (XRD). Scanning electron microscope (SEM) image showed uniformly distributed fibrous spongy like morphology. A thermal property of the polymer was evaluated by thermo gravimetric analysis (TGA). Electrochemical characterization studies were carried out to compare the improved performance of PoT modified GCE (PoT/GCE) in optimum pH1.0 under different atmospheric condition by cyclic voltammetry (CV). It was proved that the nitrogen atmosphere enhanced the electrocatalytic activity toward methanol reduction as indicated by the increased reduction peak current in linear sweep voltammetry (LSV). It has been observed that PoT/GCE has good oxygen reduction ability, and also enhances methanol reduction. Diffusion coefficient values were calculated for PoT/GCE in different atmospheric condition using Chronoamperometric and Chronocoulometric studies. The double layer capacitance value of the resistance is 1.5948 × 10−10F/cm2 which was determined by electrochemical impedance spectroscopy (EIS).

Wide-ranging application in various fields from biomedicine, catalysis and optoelectronic materials to sensors, and environmental pollution prevention by synthesising Metal oxide nanoparticles. In this present work Eco-friendly synthesis of Nickel Oxide Nanoparticles (NiO-NPs) using Avicennia Marina leaf extract in an aqueous medium. The prepared NiO-NPs were characterized by UV–Visible, FT-IR, X-ray diffraction, AFM, FE-SEM, TEM, and electrochemical techniques to find the band gap energy, functional group, grain size, morphology, and the structure, particle size respectively. UV–Vis absorption spectrum of nickel oxide nanoparticles (NiO-NPs) shows a peak in the region of 297 nm. The FTIR spectrum of NiO-NPs shows bands at 872 cm−1 and 466 cm−1. From the FESEM results, the average size of NiO-NPs is seen to be in the range of 30–100 nm. Electrochemical studies were carried out to assess the redox behavior of NiO-NPs. The obtained results confirmed the formation of nickel oxide nanoparticles from the biomaterial leaf component. The methanol oxidation of NiO-NPs has been studied by voltammetry.

Green synthesis of nanoparticles is gaining importance and has been suggested as possible alternatives to chemical and physical methods. The present work reports low- cost, green synthesis of zinc oxide (ZnO) & Ag doped ZnO nanoparticles using Vitis vinifera leaf extract. The biosynthesized nanoparticles were characterized by SEM, EDX, UV–vis, and FTIR. In the present work, the biosynthesized ZnO nanoparticle & Ag doped ZnO nanoparticles have been used for antibacterial and photocatalytic applications. The antibacterial activity of characterized samples was determined against Gram-positive and Gram-negative bacteria. The obtained results revealed that the bacterial growth decreases with increase in the concentration of biosynthesized ZnO nanoparticles. Also, Gram-positive bacteria seemed to be more sensitive to ZnO & Ag doped ZnO nanoparticles than Gram-negative bacteria. The biosynthesized ZnO nanoparticles showed photocatalytic activity under the UV light enhancing the degradation rate of methylene blue (MB), which is one of the main water- pollutants released by textile industries.

We have explored the nanocomposites as a potential catalyst material in acid medium for the electro-oxidation of methanol. Electrochemical impedance studies have shown that the Rct value of (Poly-3-Anisidine) P3A/GCE is lower than the modified P3A-metal oxide doped electrodes. In the case of doped metal oxides, we claim, this validates the slow electron transfer mechanism. Compared to P3A-MnO2, P3A-Fe2O3 catalysts, the as-synthesized P3A-Cr2O3 displays an expanded electrochemically active surface region, substantially enhanced catalytic activity and improved stability for methanol oxidation reaction (MOR).

Polymers have exhibited a promising ability for the corrosion protection of metals. In the present study, poly(o-anisidine) (POA) nanoparticles and its nanocomposites with silicon dioxide (SiO2) like POA/SiO2 containing different compositions content of SiO2 (5%, 10% & 15% w/w) were prepared by chemical oxidative polymerization. FT-IR spectra of POA/SiO2 composites indicate the presence of SiO2 nanoparticles in the polymer nanocomposites. The X-ray diffraction (XRD) studies was showed more crystalline behavior of polymer nanocomposites and the particle grain size was calculated using Scherer’s formula and it was found to be within nano range. The surface morphology of the polymer composites were investigated by Scanning Electron Microscopy (SEM). Energy dispersive X-ray spectroscopy (EDS) confirms the incorporation of silicon and oxygen in the polymer nanocomposites. Further the synthesized polymeric composites were introduced into acrylic resin and the polymer/SiO2/acrylic hybrid materials were applied on the surface of mild steel sample. The corrosion efficiency and corrosion rate of the polymer nanocomposites were calculated for mild steel in 3.5% NaCl solution using Polarization curve and Electrochemical Impedance Spectroscopy (EIS).

Nano structured metal oxides received considerable research attention due to their unique properties that can be used for designing advanced nanodevices. Thus, in the present study, Tungsten oxide/graphene oxide (WO3/GO) nanocomposite was synthesized, characterized and implemented in an electrochemical system. Graphene oxide was synthesized by Hummer’s method. WO3 doped Graphene oxide nanocomposite were also successfully synthesized using sodium tungstate as the source of Tungsten. The crystalline structure and optical properties of WO3 doped GO nanocomposite were characterized by UV–VIS spectroscopy, IR spectroscopy, X-ray diffraction (XRD) studies, Field Emission Scanning Electron Microscope (FESEM) with EDAX spectroscopy. The XRD spectrum showed diffraction peaks corresponding to the crystal planes of crystalline Tungsten oxide. Using Debye scherrer formula, the size of the undoped and Tungsten oxide doped Graphene oxide nanocomposite were also calculated. The morphological studies of the nanocomposite revealed crystal like morphology. The energy dispersive analysis confirmed the presence of Carbon, Tungsten and oxygen in the doped WO3/GO lattice. Cyclic voltammetric behaviour showed better electrochemical response with the doped sample when compared with the undoped sample.

Nano composites of conducting polyaniline with ZnS nanoparticles (PANI/ZnS) have been synthesized by in-situ polymerization of aniline monomer using ammonium persulphate as oxidizing agent. The formation of PANI/ZnS composites was assessed by UV–Vis spectroscopy, Transmission Electron Microscopy (TEM), Fourier Transform Infra-Red Spectroscope (FTIR), Atomic Force Microscope (AFM), Scanning Electron Microscope (SEM) and X ray diffraction analysis (XRD). FTIR and UV studies provided the information of functional group and optical behavior respectively SEM studies shows the well dispersion of ZnS Nanoparticles in the polyaniline matrix. Size determination identified and confirmed by TEM analysis.

Polyanilines doped with different concentrations of oxalic acid have been synthesized by oxidative chemical polymerization using potassium perdisulfate as oxidizing agent. The effect of dopant on the kinetics of polymerization has been studied by UV–VIS spectroscopy. The presence of oxalic acid in the polymer has been studied by FTIR, and morphology by SEM and TEM. The thermal stability of the polymer was investigated by TGA and degree of crystallinity of polyaniline was studied by XRD. The electrochemical behaviour has been studied by cyclic voltammetry (CV) and the phenomenon of charge transport and capacitance was examined by Electrochemical Impedance Spectroscopy (EIS). The morphological study shows the particles to be of nanosize and EIS studies show that these samples have significant double layer capacitance (Cdl) and can be used as capacitors.

Zinc oxide nanoparticles were synthesized through wet chemical method. Polyaniline was synthesized by oxidative polymerization of aniline using potassium perdisulphate as oxidizing agent. Polyaniline -Zinc oxide nanocomposites were prepared by five different percentages of zinc oxide nanoparticles mixed with synthesized polyaniline. The prepared metal oxide, polymer and Nano composites were characterized by UV–Vis, FT-IR, AFM and electrochemical studies. The FT-IR spectral studies indicated the presence of metal oxide and polymer in Nano composites. From the FT-IR spectra of Nano composites, the peak around 464 cm−1 indicated the bonding between Zn and O, the peak around 1573 cm−1 and 1503 cm−1 due to stretching vibrations of the quinonoid and benzenoid rings of polyaniline respectively. The surface morphology was characterized by AFM. The UV–Vis spectrum of polyaniline was observed five absorption bands around 230 nm, 258 nm, 299 nm, 457 nm and 632 nm. Among these five bands, the absorption band around 299 nm is assigned to the π–π* transition of the phenyl ring and another band at 632 nm is assigned to the polaron n–π* transition. The UV–vis spectral absorption intensity of Nano composites was increased as increasing of zinc oxide incorporation in polyaniline. Cyclic Voltammetric studies exhibit good sensitivity response at pH 1.0. Chronoamperometric and Chronocoulometric studies were also carried out for polymer–metal oxide nanocomposites. The present study especially aims to investigate PAni-ZnO Nano composites in order to obtain a new noble material which can be utilized for solar cell applications.

Purpose Polypyrrole (PPy) and PPy/metal oxide nanocomposites were synthesized by oxidative polymerization process, and its corrosion protection ability was studied by immersion test and electrochemical corrosion studies in 1 per cent HCl and 3.5 per cent NaCl solution. Design/methodology/approach The prepared composites were loaded in acrylic resin and subsequently coated on a mild steel surface. The characterization of the polymer composites using FT-IR, UV-vis, XRD and FE-SEM with EDS analysis confirmed the interaction between PPy and metal oxide nanoparticles. The PPy nanoparticles were less protected on the mild steel, but the nanocomposite coating with metal oxide nanoparticles dramatically increased the corrosion resistance. Findings According to the corrosion protection ability of the coating, it was demonstrated that the acrylic resin coating composed of PPy/metal oxide nanocomposites was highly efficient in protecting the mild steel compared to the PPy nanoparticles. The highest protection efficiency was obtained by PPy/TiO2 nanocomposites with acrylic resin coating. Originality/value To the best of the authors’ knowledge, this paper consists of original, unpublished work which is not under consideration for publication elsewhere and that all the co-authors have approved the contents of this manuscript and submission.

Energy is an unseen component of the world’s development and expansion. Energy storage, in addition to supplying energy from primary or secondary energy sources, such as renewables, is an important consideration. In order to meet, the demand for high-energy storage devices has grown globally as a result of rising energy consumption, and research into electrode materials for supercapacitor use has progressed. Various types of carbon-based materials have been used as electrode materials for high-performance supercapacitor applications over the years. Graphene is one of the most extensively used carbon-based materials due to its unique properties, which include a high surface area and great conductivity. To take advantage of more of its intriguing features, graphene is customised to make graphene oxide and reduced graphene oxide, which have better water dispersibility and are easy to combine with other materials to form binary or even ternary composites. Due to the fact that binary composites cannot meet the requirements of a high-performance supercapacitor, ternary composites have sparked a lot of attention recently. As a result, a variety of ways have been used to create ternary composites for high-performance supercapacitor applications by combining three different types of electroactive materials. The supercapacitive performance of graphene-based ternary composites with various active components, such as conducting polymers, metal oxide, and other carbon-based materials, is the subject of this research. The performance of graphene-based composites as electrodes in supercapacitors has been greatly improved. This article discusses the synthesis, graphene based supercapacitor electrode materials as well as the application of graphene based nanocomposites as supercapacitor application.

This short review article presents a summary of ecofriendly ways to synthesize cobalt oxide (Co3O4) nanoparticles using biomaterials like plant extract, bacterium and fungus. Currently, researchers have focused their concentration on the biosynthesis of nanoparticles using biomaterials containing phenols, carbonyls, amines, carbohydrates, proteins and amino acids which act as bio-templates, reducing agents, stabilizing agents, capping agents and chelating agents for nanoparticles. This article also discussed the reports of characterization of cobalt oxide nanoparticles by UV-Vis spectroscopy, diffuse reflectance spectroscopy (DRS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), selected area electron diffraction (SAED), scanning electron microscopy (SEM), high resolution scanning electron microscopy (HRSEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM) and Brunauer - Emmett -Teller (BET) analyzer which were carried out by various researchers. The applications of these biosynthesized cobalt oxide nanoparticles in a wide range of potential zones are listed including antibacterial activity, photo catalyst, sensor and supercapacitor.

Conducting polymer of anthranilic acid (PANA) has been synthesized through emulsion polymerization technique. Emulsion polymerization helps in slowing down kinetics of polymerization in comparison to one-phase polymerization and thereby induces formation of monodispersed. Reaction progress of conducting polymer formation is studied by UV–Vis and FTIR spectroscopy. Morphology of PANA is characterized by XRD, TEM, AFM and electrochemical techniques. XRD of conducting polymer depicts the less crystalline nature of polymer with crystallite size of 75 nm. Voltammetry has shown the electro-active nature of PANA. The performance of energy storage devices including pseudocapacitors is evaluated mostly by measuring energy density and power density.

Nanocomposite of Zinc doped Iron oxide/Graphene Oxide/Chitosan was prepared using optimized quantity of the components by simple solution mixing-evaporation method. The structure of the composite was studied by UV–Vis, FTIR, XRD, SEM, HRTEM and AFM. The results obtained from these analyses showed the formation of homogeneous mixture with strong interaction between the constituents and evidenced by the shift in peak position in both UV–Vis and FTIR spectra. Band gap calculated was found to be 2.28eV which indicates the conducting nature of the composite. The formation of composite in nano dimensions of around 20 nm was proved by XRD, SEM and HRTEM studies. Thermal stability of the sample was investigated by TG/DTA and DSC techniques and showed improved thermal stability with the increase in glass transition temperature of chitosan by 78°c. Electrochemical characteristics of the composite was studied by cyclic voltammetry and capacitative behavior was studied by impedance studies (EIS). These electrochemical investigations revealed good adherent nature of the composite on electrode surface at pH1 and greater electrochemical stability with well defined redox peaks. EIS showed that the nanocomposite modified electrode exhibited good capacitance behavior with the bode phase angle of 87° which proves it to be a very good candidate for supercapacitor applications.

Silica nanoparticles (SNPs) were synthesized using rice husk by eco-friendly method. The physico-chemical characterization of SNPs was investigated by Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). FT-IR spectrum shows the main characteristic peak of Si O Si at 468 cm−1 indicating the formation of SNPs. The XRD pattern revealed the formation of crystalline SNPs and the particle grain size value were found to be 5 nm. The surface morphology was observed by SEM. EDS result showed that the composition of silicon and oxygen in SNPs is found to be 47.54% and 28.24%, respectively. Acrylic coating containing SNPs was directly coated on the mild steel surface and the anticorrosive behavior was examined by polarization curve and electrochemical impedance spectroscopy in 1% HCl and 3.5% NaCl solution. It was found that silica/acrylic coating showed better corrosion protection efficiency as compared to that of pure acrylic coating. Silica/acrylic coating acted as good anticorrosive behavior for 3.5% of NaCl solution.

The growth of industry fulfills our necessity and promotes economic development. However, pollutants from such industries pollute water bodies which pose a high risk for living organisms. Thus, researchers have been urged to develop an efficient method to remove toxic heavy metal ions from water bodies. The adsorption method shows promising results for the removal of heavy metal ions and is easy to operate on a large scale, thus can be applied to practical applications. Numerous adsorbents were developed and reported, among them hydrogels, which attract great attention because of the reusability, ease of preparation, and handling. Hydrogels are generally prepared by the cross-linking of polymers that result in a three-dimensional structure, showing high porosity and high functionality. They are hydrophilic in nature because of the functional groups, and are non-toxic. Thus, this review provides various methods of hydrogel adsorbents preparation and summarizes recent progress in the use of hydrogel adsorbents for the removal of heavy metal ions. Further, the mechanism involved in the removal of heavy metal ions is briefly discussed. The most recent studies about the adsorption method for the treatment of heavy metal ions contaminated water are presented.

A glassy carbon electrode (GCE) was modified with nanosize poly (3-methylthiophene) (P3MT) and used for the sensitive voltammetric determination of diazepam. The cyclic voltammetric response of the bare GCE was compared with the P3MT modified electrode. Electrochemical impedance response of diazepam on modified GCE was studied by various concentrations of diazepam from 0.2 μM to 0.6 μM. The poly (3-methylthiophene) modified glassy carbon electrode (P3MT/GCE) can greatly enhance the peak currents and the detection sensitivity of diazepam under optimal conditions. The quantitative analysis of diazepam was made by the DPSV method. The experimental results showed that the peak current increased with the increase in concentration of diazepam. A calibration was made, which indicated the linear dependence of peak current with concentration (ip = 13.31Conc. + 0.4359R2 = 0.9948) in the range od determination and ot was found to be good between 0.2 and 1.07 μg/L. The limit of detection was 0.1μg/mL. The reproducibility of the stripping signal was realized in terms of relative standard deviation for 6 identical measurements and was found to be 2.6%. The effect of interference of different cations and anions on the oxidation of diazepam was studied. Real sample analysis of diazepam was also studied through DPSV.

Toluidine was polymerized with montmorillonite (Mt) by the chemical oxidation method using potassium perdisulfate by varying the toluidine to clay ratio. The solubility of the chemically prepared clay-polymer nanocomposites (CPN) was ascertained and it showed good solubility in DMSO and DMF. The in situ intercalative polymerization of o-toluidine (POT) within the Mt layers was analyzed by FTIR, UV–visible, XRD, SEM and TEM. The analyses of UV visible and FTIR spectroscopy demonstrated that o-toluidine has been polymerized to POT in its conducting emeraldine form. The conformation adopted by POT chains in the Mt interlayer depended on the molar ratio of o-toluidine to montmorillonite. FTIR spectra showed that amine vibration peak observed at 1593 cm− 1 was shifted to lower wave numbers when the CPN were formed. SEM analysis showed the variation in morphology from granular agglomerate to layered flaky structure as the clay mineral concentration was increased. Elemental analysis was done by EDAX which shows the presence of Na, Mg Al, Si, C and N. Thermal stability of the CPN was studied using TGA/DTA and DSC studies. The X-ray diffraction studies revealed the formation of nano sized (28 nm) crystalline CPN. Cyclic voltammetric studies of the synthesized CPN exhibited good adherent behavior on electrode surface at pH 1.0. It exhibited one oxidation peak at 0.405 V and one reduction peak at 0.299 V. By varying the atmosphere it was found that the CPN modified electrode exhibited oxygen reducing capacity.

Aniline was polymerized with TiO2 by chemical oxidation method using Potassium perdisulphate. The solubility of the chemically prepared polymer–ceramic nanocomposite was ascertained and it showed good solubility in DMSO and DMF. The Pani–TiO2 nanocomposite was characterized by UV–Vis, FTIR spectral studies. Amine vibration observed at 1593 cm-1 was shifted to lower wave numbers when the polymer–ceramic nanocomposites were formed. The X-ray diffraction studies revealed the formation of nano sized (26 nm) crystalline polymer. SEM analysis showed mixed granular nature of the polymer–ceramic nanocomposite. EDAX analysis shows the presence of Ti, C and N. Cyclic Voltammetric studies exhibit good adherent behaviour on electrode surface at pH 1.0. It showed the presence of oxidation peaks at 0.271V and 0.623V and reduction peaks at 0.832 and 0.493V. CV, Chronoamperometric and chronocoulometric studies were also carried out at inert as well as oxidation atmosphere.

Nano CuO-ZrO2 mixed oxides were prepared by wet chemical method by mixing equimolar solutions (0.45M) of cupric chloride (1.92g) and Zirconium oxychloride (3.63g) in aqueous Sodium hydroxide and refluxed at elevated temperature. The prepared nano CuOZrO2 mixed oxides were characterized by FT-IR, SEM, EDAX, XRD, DSC and CV studies. From XRD studies the size of the nano CuO and ZrO2 are found to be 25 and 9.5nm respectively through Debye-Scherrer's formula. The sizes of the CuO-ZrO2 mixed oxide particles have also been characterized and the average grain size of the particles is found to be 24nm in diameter. The nano particle composition and morphology of CuO, ZrO2 and mixed oxide have been analysed by EDAX set up attached with scanning electron microscope (SEM). EDAX analysis indicates the presence of Cu, Zr and O. SEM morphological studies of CuO, ZrO2 and mixed CuO-ZrO2 revealed the particle distribution with uniform granular structure. Cyclic Voltammetric studies exhibit good adherent behaviour on electrode surface and good electroactivity at pH 1.0. Nano CuO, ZrO2 and mixed CuO-ZrO2 under goes oxidation at 0.224V, 0.092V -0.072V and0.198V respectively. DSC thermogram of CuO, ZrO2 and mixed CuO-ZrO2 are recorded at the heating rate of 10o/ min. The glass transition temperature (Tg), the crystallization temperature (Tc) and melting point (TM) of the mixed oxide are determined from the DSC curve. The Tg value of CuOZrO2 mixed oxide is -50o C the Tc value is 20o C and melts at a temperature of 116o C.

Nano size Polypyrrole (PPY) was synthesized electrochemically in presence of three different surfactants namely CTAB, CSA and TTX-100. Cyclic voltammetric studies showed an irreversible oxidation of pyrrole in the presence of surfactants. The currents of the broad peak were 4.26mA, 5.3mA and 8.6mA for PPY/CTAB, PPY/CSA and PPY/TTY-100 respectively. The FT IR spectra of electrochemically synthesized PPY in presence and absence of surfactants were analyzed and the prominent peaks were assigned properly. The presence of N-H group in both cases suggests the presence of pyrrole units in the polymer. From the XRD results the particle sizes of all the four PPYs were determined and the values are as follows: PPY (34 nm), PPY/CSA (31 nm), PPY/CTAB (30nm), PPY/TTX-100 (29 nm). The PPY/TTX-100 exhibited highest electrical conductivity (2.04 ×10−3 S/cm) among other PPY synthesized (PPY/CTAB - 1.13 ×10−3 S/cm, PPY/CSA - 1.09×10−3 S/cm and PPY - 1.27 ×10−3 S/cm). SEM images of PPY/CSA showed agglomerated small polymeric fragments whereas PPY/CTAB showed large sized polymeric plates. Interestingly PPY/TTX–100 showed uniform hollow structure. The presence of surfactants has resulted in uniform polymer formation.

3,4-Ethylenedioxy thiophene is polymerized electrochemically in p-toluene sulphonic acid (a), phosphate buffer (b) and borax buffer (c) on glassy carbon and Indium tin oxide (ITO) surface. The scan rate dependence studies of the polymer redox processes were carried out. A linear relationship was observed between the peak current and scan rate with good correlation, r2 = 0.998 indicating adsorption controlled behaviour of polymer film. The SEM photograph showed the differences in surface morphology of polymers modified electrode. The XRD studies revealed semi-crystalline nature of doped polymers. Spectroelectrochemical behaviors of Indium tin oxide coated glass electrode covered with thin film of poly-3,4-ethylenedioxythiophene a, b, c in 0.1 M KCl were obtained at different electrode potentials between 1100 and 200 nm. Poly-3,4-ethylenedioxythiophene-a, poly-3,4-ethylenedioxythiophene-b and poly-3,4-ethylenedioxythiophene-c film exhibits transparent clear blue, opaque violet and dark maroon colours respectively at reduced potential. Further probing the potential between 400 mV and 800 mV coated film shows greenish blue colour for poly-3,4-ethylenedioxythiophene-a, poly-3,4-ethylenedioxythiophene-b and poly-3,4-ethylenedioxythiophene -c shows opaque violet and yellowish maroon colours respectively. Increasing the applied potential between 1000 mV and 1200 mV over oxidation of polymer film shows dark greenish blue for poly-3,4-ethylenedioxythiophene -a, dark brown for poly-3,4-ethylenedioxythiophene-b and transparent red colour for poly-3,4-ethylenedioxythiophene-c. Electrochromic parameters such as colouration efficiency, response time and optical contrast were calculated for all three films.

Nano particles of Copper oxide and Poly(3,4-ethylenedioxythiophene)-Copper oxide nanocomposite were prepared by chemical oxidation method. The formed metal oxide nanoparticle and polymer metal oxide nanocomposites were characterized by UV–VIS, XRD, SEM and EIS studies. The UV-VIS studies of nanoparticles and nanocomposites exhibited four peaks, two peaks are sharp and centered at 280nm and 360 nm while the other two were broaden waves obtained at 780nm and 985nm. SEM image of copper oxide nanoparticles and nanocomposite exhibits sponge-like morphologies, in addition to nanospheres, nanowires, and nanotube shapes. The grain size of the metal oxide nanoparticle and polymer metaloxide nanocomposites was calculated using Scherrer’s formula. Electrochemical impedance spectroscopy (EIS) studies revealed the high conductivity nature due to the increased surface area of the nanocomposites.

Aniline was polymerized with mmt (Montmorrillonite) by chemical oxidation method using potassium perdisulphate. The solubility of the chemically prepared polymer–clay nanocomposite was ascertained and it showed good solubility in DMSO and DMF. The Pani–mmt nanocomposites were characterized by UV–Vis, FTIR spectral studies. Amine vibration peak observed at 1593 cm-1 was shifted to lower wave numbers when the polymer–clay nanocomposites were formed. The X-ray diffraction studies revealed the formation of nano sized (26 nm) crystalline nanocomposite. SEM analysis showed mixed granular nature of the polymer–clay nanocomposite in which polymer was intercalated with the clay. EDAX analysis shows the presence of Na, Mg Al, Si, C and N. Cyclic Voltammetric studies exhibit good adherent behaviour on electrode surface at pH 1.0. It exhibited two oxidation peaks at 0.360V and 0.638V and two reduction peaks at 0.431V & 0.103V. Chronoamperometric and chronocoulometric studies were also carried out at inert as well as oxidation atmosphere.

Nearly perfect single crystal of L-tyrosine hydrobromide (LTHB) has been grown at room temperature from the saturated solution prepared from the solvent with optimised normality (2N) using slow evaporation solution growth technique. Crystal system and lattice parameters have been estimated by single crystal X-ray diffraction analysis. Prominent peeks of powder X-ray diffraction pattern have been indexed and diffraction data have been presented. The presence of various functional groups in LTHB has been identified by vibrational and Nuclear Magnetic Resonance spectral study. The crystalline nature and defect during the growth has been studied by obtaining high resolution X-ray diffraction curve (rocking curve) for the title crystal and detailed explanation is given in this paper. Cyclic voltammetric behaviour and photoluminescence properties of LTHB have also been investigated.

Nearly perfect single crystals of l -histidine hydrochloride monohydrate have been grown from the solution prepared from the mixture of l -histidine and hydrochloric acid using slow evaporation solution growth technique. Single crystal X-ray diffraction analysis, High resolution X-ray diffraction analysis, fourier transform infrared and FT-Raman analyzes were employed for structural characterization. Linear and nonlinear optical properties have been studied by UV–Vis transmission spectrum and Kurtz Perry technique respectively. The refractive index, redox behavior and hardness of the grown crystal have been found by suitable methods. Thermogravimetric, differential thermal analysis were employed to characterize the as-grown crystals. The second harmonic generation conversion efficiency of the grown crystal and other properties show the suitability of the grown crystal for frequency conversion applications.

Intrinsically conducting polymer metal nanocomposites were synthesized by polymerising anthranilic acid (PANA) with metal salts like ferric chloride, Zinc oxide and Magnesium oxide by chemical oxidation method. Polyanthranilic acidiron nano composite (PANA-Fe), Polyanthranilic acid-Zinc nano composite(PANA-Zn) and Polyanthranilic acid-magnesium nano composite (PANA-Mg) synthesized were characterised by UV-Visible and FTIR studies. FTIR spectra of polymer-metal nano composites showed peaks in the region between 1690 cm-1 and 1490 cm-1 which corresponds to the deformation in different types of N-H bond. The participation of the -NH group in polymerization was confirmed by the appearance of a peak around 3431 cm-1. Cyclic voltammetric studies revealed the presence of an adherent polymer film on the glassy carbon electrode and showed redox behavior of the polymer metal nanocomposites. The XRD (XRay Diffraction) studies showed a rather more crystalline behaviour of the nano composites and the grain size was calculated using Scherrer’s formula and it was found to be in nano range. SEM (Scanning Electron Microscope) analysis showed a rather mixed crystalline and amorphous behavior. EDAX (Energy Dispersive X Ray Spectroscopy) confirms the incorporation of the metals iron, Zinc and Magnesium in the polymermetal nano composites. The inhibition efficiency of the polymermetal nano composites were calculated for stainless steel in acidic environment using elec-trochemical impedance spectroscopy (EIS) and polarization (Tafel) studies and the prepared PANA-Fe and PANA-Zn nano composites showed effective anti-corrosive behavior on stainless steel in acid medium.

Three analgesics, acetaminophen, acetylsalicylic acid, and dipyrone were determined by stripping voltammetry using nanosized poly(3,4-ethylenedioxythiophene)-modified glassy carbon electrode . The cyclic voltammetric behavior of the three analgesics was studied in aqueous acid, neutral, and alkaline conditions. One well-defined oxidation peak each for acetaminophen and acetylsalicylic acid and three oxidation peaks for dipyrone were observed in the cyclic voltammograms. The influence of pH, scan rate, and concentration revealed irreversible diffusion controlled reaction. A systematic study of the experimental parameters that affect the differential pulse stripping voltammetric response was carried out. Calibration was made under maximum peak current conditions. The scanning electron microscope analysis confirmed good accumulation of the drugs on the electrode surface. The range of study for both acetaminophen, acetylsalicylic acid were 0.015–0.4 and dipyrone was 0.025–0.4 μg/ml. The lower limit of determination for both acetaminophen, acetylsalicylic acid was 0.01 μg/mL and for dipyrone was 0.02 μg/mL. The suitability of the method for the determination of the three analgesics in pharmaceutical preparations and urine samples was also ascertained.

Pheniramine maleate (PA), an antihistamine, was determined by Differential Pulse Stripping voltammetry using nano polypyrrole (Ppy) and nano poly(3,4-ethylenedioxythiophene) (PEDOT) modified glassy carbon electrodes. The cyclic voltammetric behavior of pheniramine was studied in aqueous acidic, neutral and alkaline conditions. One well-defined oxidation peak was observed in the cyclic voltammograms at all pHs. The influence of pH, scan rate and concentration revealed irreversible electron transfer and the oxidation was diffusion controlled adsorption. The SEM analysis confirmed good accumulation of PA on the electrode surface. A systematic study of influence of various experimental parameters that affect the stripping voltammetric response was carried out and the maximum peak current conditions were arrived at. Calibration was made under maximum peak current conditions. The range of study was 0.05 to 0.4 μg/mL on Ppy/GCE and 0.025 to 0.4μg/mL on PEDOT/GCE and the lower limit of determination were 0.035μg/mL on Ppy/GCE and 0.016μg/mL on PEDOT/GCE. The suitability of the method for the determination of PA in pharmaceutical preparations and urine samples was also ascertained.

4, 4′-Diaminodiphenyl sulphone was polymerized (with lithium/cobalt/lithium–cobalt salts) by chemical oxidation method using potassium perdisulphate. The solubility of the chemically prepared polymer–metal nanocomposite was ascertained and it showed good solubility in DMF, chloroform, trichloroethylene and DMSO. The PDDS–Li/Co/Li–Co nanocomposites were characterized by UV–vis and FTIR spectral studies. Amine and imine vibrations observed at 1593 and 1503 cm −1 were shifted to lower wave numbers when the polymer–metal composites were formed. A single absorption peak due to the N–H stretching vibration of the imino groups of polymer–metal nanocomposite is observed around 3459 cm −1 and it suggests the participation of NH group during polymerization. The X-ray diffraction studies revealed the formation of nano sized (82 nm) crystalline polymer. The conductivity of the PDDS–Li–Co nanocomposite was determined to be 6.26 × 10 −2 S cm −1 . SEM analysis showed mixed granular nature of the polymer–metal nanocomposite. The capacitance (159.04 μF) of chemically synthesized PDDS–Li–Co nanocomposite is suggested as a potential capacitive material.

The reactive yellow 107 was polymerized by chemical oxidation method using potassium persulfate. The polymer was characterized by UV-VIS and Fourier transform infrared spectroscopy (FTIR) spectral studies. The peaks at 2,922 and 2,852 cm−1 in the FTIR spectrum of polyreactive yellow 107 are assigned to the symmetric and asymmetric stretching vibrations of CH2. The peak observed at 1,583 cm−1 for polyreactive yellow 107 may be assigned to the stretching vibration of C=O, N=N, and C=C, 1,347 cm−1 stretching vibration of C–N. The stretching vibrations of sulfone and sulfonic acid of S=O groups show a strong broad peak at 1,091 and 1,051 cm−1. The conductivity of the polymer was determined to be 5.57 × 10−5 S cm−1. The solubility of the chemically polymerized powder was ascertained and polyreactive yellow 107 showed good solubility in N,N-dimethyl formamide and dimethyl sulfoxide. The X-ray diffraction studies revealed the formation of nano-sized (84 nm) crystalline polymer. Using X-ray diffraction, behavior strain and dislocation density was also calculated. Scanning electron microscope analysis showed uniform crystalline nature of the polymer (200 nm). The thermogravimetric analysis, differential thermal analysis, and differential scanning calorimetry studies revealed good thermal stability of the polymer.

Three analgesics (acetaminophen, acetylsalicylic acid, and dipyrone) were determined electrochemically using nano polypyrrole modified glassy carbon electrode. The cyclic voltammetric behavior of the three analgesics was studied in aqueous acid, neutral, and alkaline conditions. One well-defined oxidation peak each for acetaminophen and acetylsalicylic acid and three oxidation peaks for dipyrone were observed in the cyclic voltammograms. The influence of pH, scan rate, and concentration reveal the irreversible diffusion controlled loss of 4e− in acid and neutral media and 2e−/1H+ in basic medium for acetaminophen. In the case of acetylsalicylic acid, 2e− and 1H+ loss in acidic and neutral pH and 2e− and 2H+ loss in basic pH were observed and the oxidation was irreversible and controlled by adsorption. Irreversible removal of 2e− and 1H+ in all pH media was observed for dipyrone and the oxidation was controlled by diffusion. A systematic study of the experimental parameters that affect the differential pulse stripping voltammetric response was carried out and optimized conditions which yield maximum peak current were arrived at. Scanning electron microscopy (SEM) analysis confirms good accumulation of the drugs on the electrode surface. The calibration was made under optimum conditions. The range of study for acetaminophen, acetylsalicylic acid, and dipyrone was 50–250, 40–300, and 100–400 ng/mL and the lower limit of determination was 45, 25, and 70 ng/mL respectively. The suitability of the method for the determination of the three analgesics in pharmaceutical preparations and urine samples was also ascertained.

Three analgesics were studied voltammetrically using a sodium montmorillonite (NaMM) modified glassy carbon electrode. The voltammograms of analgesics were studied in pHs 1.0–13.0. Influence of pH, sweep rate and pharmaceutical formulations concentration were studied. One well-defined oxidation peak was observed for acetaminophen (AAP) and acetylsalicylic acid (ASA), three oxidation peaks for dipyrone (DP). The oxidation peak potential shifted towards negatively with change in pH. The oxidation was irreversible and diffusion-controlled for all pharmaceutical samples of acetaminophen, dipyrone, and acetylsalicylic acid. A systematic study of the experimental parameters that affect the square wave stripping voltammetric response was carried out and optimized conditions were arrived at. Under optimum conditions, stripping voltammetric procedure was developed for the determination of analgesics in pharmaceutical and urine at pH 1.0. A calibration plot was derived and the lower limit of determination was noticed as 0.02 μg mL − 1 for acetylsalicylic acid, 0.02 μg mL − 1 for acetaminophen and 0.04 μg mL − 1 for dipyrone. The percentage of rsd was also found.

Electroanalytical determination of heavy metals using stripping voltammetry is commonly employed and has many advantages over other methods. The sensitivity of the technique is greatly improved by employing different modified electrodes. Seven novel polymer-modified glassy carbon electrodes have been developed in this investigation for the trace analysis of heavy metals such as zinc, cadmium, lead, arsenic, and copper in formulated samples of waters by square wave stripping voltammetry. Very good responses have been observed for all the metals, while all the modified electrodes employed. The poly(3,4-ethylenedioxythiophene)-modified electrode has resulted in very low limit of detection (LOD) value. Comparison is made between literature results of LOD and the results obtained in this study. An independent atomic absorption spectroscopic analysis of the industrial wastewater sample was carried out and the results compared. The suitability of the method for practical application was ascertained by applying the procedure for the wastewater from a plating industry.

Seven novel polymer modified glassy carbon electrodes have been developed for the analysis of metals of zinc, cadmium, lead, arsenic and copper in formulated samples of waters and industrial wastewater samples by differential pulse stripping voltammetry. Very good responses have been observed for all the metals with all the modified electrodes employed. However, the poly(3,4-ethylenedioxythiophene) modified electrode has resulted in very low detection limits. An independent atomic absorption spectroscopic analysis of the industrial wastewater sample was carried out and the results are compared.

Copolymer of 3,4-ethylenedioxythiophene (EDOT) and diclofenac (DCF) was synthesized by chemical oxidation using FeCl3 in neutral medium. The copolymer exhibited good solubility in many organic solvents. The UV-vis spectrum of the copolymer revealed the presence of benzenoid and polaron or bipolaron state. Random distribution of the monomers in the copolymer was proposed based on the reactivity ratios of the monomers determined using Fineman-Ross and Kelen-Tudos methods. The rate of the copolymerization depended on the first power of each monomer. The FTIR spectrum showed the presence of hydrogen bonded N-H, quinone type structure of thiophene ring and C-Cl bond in the copolymer. Linear variation of anodic peak current at 560 mV in the cyclic voltammogram of copolymer thin film with scan rate indicated the adherence of electroactive copolymer. When the applied potential increased from −600 to 1000 mV, the color of the copolymer changed from neutral yellow to brown and to violet medium showing multicolor electrochromic behaviour. XRD results revealed crystallite copolymer with size 87 nm. SEM analysis confirmed uniform crystalline nature of the copolymer. The TGA, DTA and DSC studies suggested good thermal stability of the copolymer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2787–2796, 2007

Electrochemical polymerization of 3,4-ethyl- enedioxythiophene (EDOT) was carried out in presence of two different surfactants, sodium dodecyl sulfate (SDS) and cetyl trimethyl ammonium bromide (CTAB) in aque- ous medium. The cyclic voltammograms of the polymers exhibited well-defined redox peaks at Eox ¼ 140 mV, Ered ¼ 360, and � 180 mV for PEDOT/SDS and Eox ¼ 360 mV, Ered ¼ 540, � 140 mV for PEDOT/CTAB. The electroactive polymer showed good adherence. The spectroelectrochemical studies were carried out on ITO glass plate at various applied potentials. The oxidized PEDOT/CTAB was opa- que blue in color and the reduced form was transparent yellow in color. Electrochromic parameters such as elec- trochromic efficiency (or coloration efficiency), stability (or cycle life), and optical contrast (or write-erase effi- ciency) and stability were determined and presented. The in situ conductance was measured at applied potentials ranging from � 0.6 V to 0.7 V. The polymer was resistive initially at � 0.6 V (7.5 � 10 � 5 Sc m � 1 )a nd reached maxi- mum conductance of 1.7 � 10 � 3 Sc m � 1 at 0.5 V in pres- ence of SDS. The polymer formed with CTAB exhibited high resistive behavior. The surface morphology charac

Aniline was copolymerized chemically in presence of five different concentrations of 4,4′-diaminodiphenyl sulphone using potassium persulphate. The copolymer exhibited good solubility in DMF and DMSO. Copolymers were characterized by UV–VIS, FTIR, XRD and SEM studies. The formation of polymer through N–H group was understood from the single N–H stretching vibrational frequency at 3378 cm −1 and bands at 1630 and 1494 cm −1 for quinonoid and benzenoid structures, respectively. The stretching vibration of sulphone S O at 1115 cm −1 clearly indicated the presence of DDS in the copolymer. The X-ray diffraction studies revealed the formation of nano sized crystalline copolymer. When more DDS was incorporated in the copolymer the crystalline nature changed from less to more. The grain size of the copolymer calculated from Scherrer's formula was 83 nm. The nano size copolymer formation was also confirmed through surface morphology (100 nm) studies. The electrical property of the copolymer was studied by four-probe conductivity meter. The synthesized polymers have conductivity of 7.21 × 10 −3 to 2.07 × 10 −3 S cm −1 . The voltammetric and spectroelectrochemical results were also presented.