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The purpose of this paper is to produce non-conductive copolymers of N-vinyl carbazole (NVCz) and methyl ethyl ketone formaldehyde resin (MEKFR) by the electroinduced Ce (IV) polymerization method and the electrochemical oxidization of the formed copolymer to produce their conductive green form. The non-conductive and conductive copolymers were characterized by using Fourier transform infrared, solid-state conductivity and spectroelectrochemical, chronoamperometric, cyclovoltammetric and electrochemical impedance spectroscopic measurements.

The chronoamperometric electropolymerization of white, insulator form of the copolymer of NVCz and MEKFR (copolymer 1) on to Pt electrode was carried out and the green coloured film of the MEKFR-ox-NVCz copolymer (copolymer 11) was produced in the doped and conductive form. All reactions were performed in dichloromethane containing 0.1 M B_U4NClO₄. Copolymer 11 films obtained on the surface of the working electrode were removed and washed in acetonitrile and dried at room temperature before characterization. The results were compared with the copolymer obtained by electrochemical oxidation of MEKF-R and NVCz (copolymer 2).

The insulating copolymer of NVCz and MEKFR (copolymer 1) was produced by the electroinduced Ce (IV) polymerization method and converted into the conductive form electrochemically on the surface of the Pt electrode (copolymer 11). The polymers were characterized by electrochemical, spectrophotometric and conductivity measurements. The ionization potentials, optical band gap, peak potentials Ep, doping degree and specific capacitance of the copolymer 11 were obtained. The conductivity of the copolymer 11 is lower than the PNVCz and higher than the copolymer obtained by electrochemical oxidation of MEKF-R and NVCz (copolymer 2). The copolymer 11 has a lower onset potential than PNVCz and the copolymer 1 and slightly higher band gap than PNVCz. The capacitive behaviours of the copolymer 11 were very close to PNVCz.

This study focuses on obtaining a green and conductive form of the copolymer of NVCz and MEKFR with the electrochemical method by using a white and insulator form of the same copolymer.

This work provides technical information for the synthesis of conducting copolymer of NVCz and MEKFR.

These copolymers may be in the field of PNVCz applications such as photoconductivity and corrosion inhibition.

Electroinduced Ce (IV) MEKFR redox system was applied for the polymerization of NVCz monomer to produce the copolymer 1. The conductive copolymer 11 was synthesized through electrochemical oxidative coupling of the carbazole groups of the copolymer 1.

The purpose of this paper is to improve the conductivity and processability of polyaniline (PANI).

The study opted for synthesis of the conductive PANI/polyvinyl alcohol (PVA) composite film, co-doped with 5-sulphosalicylic acid and sulphuric acid. Using an electrochemical method, a small amount of silver (Ag) was electrodeposited on the film. The PVA/PANI and PVA/PANI/Ag composite films were characterised by scanning electron microscope, X-ray diffraction and infrared. The composite deposition mechanism of the composite film was investigated by cyclic voltammetry for the first time.

The conductivity of the optimum PVA/PANI composite film reached 21.2 S · cm⁻¹.Then, a small amount of Ag was deposited on the PVA/PANI film, and the conductivity significantly increased by 1250 S · cm⁻¹. Through appropriate degree of stretching, the conductivity of the films was enhanced. The results indicate that uniform PVA/PANI fibres and dendritic Ag can combine to form complete three-dimensional conductive networks that exhibit better conductivity and mechanical properties. The cyclic voltammetry curves reveal that the dedoping potential of PANI was more negative than the reduction potential of Ag. Therefore, the procedure for the deposition of Ag on the PANI/PVA composite film cannot decrease the conductivity.

This paper for the first time described and revealed the effective and practical synthesis approach and composite mechanism to prepare multi-types metal-conductive polymer composites and improve the conductivity of a conductive polymer with a less expense and one-step electrochemical method.

This paper first explored galvanostatic oxidation to synthesise a PANI composite film to resolve the processability and conductivity of PANI by co-doped with mixed acids and deposited Ag on film. Furthermore, for the first time, the composite mechanism of metal and conductive polymer was studied.

This paper aims to investigate the electrocatalytic activity of CoFe_1.9Mo_0.1O₄-Ce_0.8Gd_0.18Ca_0.02O_2-δ composite (CFMo-CGDC) for the direct synthesis of ammonia from H₂O and N₂ under atmospheric pressure.

CoFe_1.9Mo_0.1O₄ nanoparticles (CFMo NPs) were synthesized via a sol-gel method. CFMo NPs were characterized using X-ray diffraction (XRD), Brunauer–Emmet–Teller (BET) specific surface area measurement and scanning electron microscope (SEM). Double-chamber reactor was used to synthesize ammonia using H₂O and N₂ as precursors. The factors affecting the ammonia formation rate (applied voltage and temperature) were studied.

CoFe_1.9Mo_0.1O₄ nanoparticles (CFMo NPs) were synthesized via a sol-gel method. CFMo NPs were characterized using XRD, Brunauer–Emmet–Teller (BET) specific surface area measurement and SEM. Double-chamber reactor was used to synthesize ammonia using H₂O and N₂ as precursors. The factors affecting the ammonia formation rate (applied voltage and temperature) were studied.

The usage of CFMo-CGDC composite as an electrocatalyst for the synthesis of ammonia directly from H₂O and N₂.

The paper introduces a microwave and electrochemical-assisted method for synthesis of chlorine-derived iron phthalocyanine pigment and oxygen reduction reaction catalyst nanoparticles. The aims of this study are to investigate the possibility of nano-scale particle size (<35 nm), high-efficiency product reaction, remove acidic wastewater, time optimization and maximize number of chlorine on aromatic rings.

The paper presents a combined synthesis technique, which does not have the problems of the conventional methods. Chlorinated iron phthalocyanine nanoparticles have been fabricated using phthalic anhydride, urea (high purity), electrochemical-generated iron (II) cations and microwave irradiation as promoter. The approach yields a product of high quality, uniform particle size distribution and high efficiency and that was environment-friendly.

The particle size and time needed for the production of chlorinated iron phthalocyanine were about 35 nm and 7 min, respectively.

The catalyst, that is used in this method, should be weighed carefully. In addition, the solvent should be a saturated solution of NaCl in water.

The method provides a simple and practical solution to improving the synthesis of an iron-based catalyst for oxygen reduction reaction.

The combined method for synthesis of chlorinated iron phthalocyanine was novel and can find numerous applications in the industry, especially as an oxygen reduction reaction non-precious metal catalyst.

The overall purpose of this research paper largely depends on developing an easy method to synthesis a material suitable for supercapacitor application. This paper includes the synthesis of, α-Co(OH)₂, its structural, elemental and morphological properties and its supercapacitor properties.

Firstly, the electrolyte is prepared using binder free method, then electrodeposition is used to synthesize α-Co(OH)₂ at 2 V. X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM) are used to study the structural, elemental and morphological characteristics. The supercapacitor properties are investigated by using cyclic voltammetry, charging-discharging graph, stability test and electrochemical impedance spectroscopy (EIS).

Synthesis of α-Co(OH)₂ is a tedious job as the temperature and use of weak base plays an important role. However, throughout electrodeposition, temperature is maintained using a water bath and weak base as the precursor. The presence of nitrate anions shows more interlayer space than that of ß-Co(OH)₂ because of which free diffusion of the electrolyte is possible. Sheets structures are more visible in SEM images. Nanosheet like structure is observed in the film and such kind of structure provide higher surface area and higher specific capacitance. Usually, the surface morphology of cobalt hydroxide shows flower-like, spherical and nanocubes particles. The cross-section of the deposited film and it is found to be approximately 100 µm. In the forward and backward scan, oxidation and reduction peaks are clearly visible. However, such a behavior is reported as stable because of no further peaks of oxidation.

XRD and EDS confirms the growth of α-Co(OH)₂. SEM images shows the porous nature of the film. Specific capacitance and energy density has been estimated at 5 mV s⁻¹ is 780 F g⁻¹ and 82 W h kg⁻¹, respectively. The film was stable for 600 cycles showing 75 per cent capacitance retention. The voltage drop is 0.02 V for 0.5 A cm⁻², indicating low resistance and good conductivity of the film. The specific power is estimated to be 15 W kg⁻¹ for 1 A cm⁻². The value of R_ESR, R_CT, C_DL and W is 4.83 Ohm, 1.273 Ohm, 0.00233 C and 0.717, respectively. Thus indicating α-Co(OH)₂ to be better candidate for supercapacitor applications.

The purpose of this paper is to synthesize polypyrrole/SiO₂ composite coating on 316 stainless steel (316SS) by cyclic voltammogram and preliminary do research about the valuable effects of SiO₂ particle incorporation within the polymer matrix.

This study is based on elaboration of coating by electrochemical process and of SiO₂ by a sol-gel process.

Electrochemical impedance studies revealed that compared with polypyrrole (PPy), PPy-SiO₂ coating acts as a more protective layer on 316SS against corrosion in 3.5 per cent NaCl. Scanning electron microscopy studies revealed that the PPy-SiO₂-coated 316SS showed more uniform and compact morphology.

To fully disperse SiO₂, a sol-gel method is used. Hydroxyl group is generated on the surface of inorganic particle by the sol-gel method, which improves the inorganic particle dispersion.

The purpose of this paper is to synthesise cyclohexanone formaldehyde resin (CFR)‐modified carbazole‐9‐carbonyl chloride (CzCl) via hydroxyl groups of CFR. This carbazole‐modified resin (Cz‐CFR) comonomer was characterised by common techniques such as UV, NMR, FTIR, fluorescence spectrophotometer, and scanning electron microscopy. The oxidative and electrochemical polymerisation of CzCl‐modified cyclohexanone formaldehyde resin (Cz‐CFR) were carried out.

Cz‐CFR comonomer was synthesised by the esterification reaction of CzCl and hydroxyl groups of CFR. Then, for the chemical polymerisation, ceric ammonium nitrate (CAN)/DMF solution was added to the comonomer/DMF solution. The precipitate was filtered, washed with chloroform and dried. For the electrochemical polymerisation, potentiodynamic electrodeposition of Cz‐CFR comonomer in dichloromethane on to Pt was carried out.

The concentration effect of CAN and Cz‐CFR on the conductivity, yield, solubility and T_g values of the polymers (P(Cz‐CFR)) were investigated. Spectrophotometric (UV‐visible, NMR), and cyclovoltammetric, polarisation curves, solid‐state conductivity and in situ spectroelectrochemical measurements were performed for the characterisation of homopolymer (polycarbazole (PCz)) and P (Cz‐CFR) films comparatively. The ionisation potentials (I_p), electron affinity (E_a), optical band gap (E_g), peak potentials (E_p), doping degree (y), and specific capacitance (C_sp), of polymer films were calculated from the results of polarisation curves, cyclovoltammetry and electrochemical impedance spectroscopy.

This paper focuses on obtaining a conductive polymer by using a fluorescence comonomer, which is an insulator.

This work provides technical information for the synthesis of fluorescence comonomer and conducting an alternative polymer.

The paper describes how a new Cz‐CFR comonomer was synthesised. This comonomer has a higher T_g value than CFR alone and also has fluorescence property. Cz‐CFR was polymerised by ceric salt and by electrochemical polymerisation. The band gap of the copolymer is not remarkably lower than polycarbazole.

The main purpose of the present study is to introduce new Schiff bases as corrosion inhibitor for carbon steel in 1 M HCl. The inhibitory activity of Schiff base was also assessed.

2,2′-((1Z,1′Z)-((2,2-dimethylpropane-1,3-diyl)bis(azanylylidene))bis(methanylylidene))diphenol was synthesized and it’s performance as an inhibitor was then investigated in 1 M HCl. The inhibition of this compound was studied and evaluated by the chemical methods of electrochemical impedance spectroscopy, electrochemical potential dynamic polarization and Atomic Force microscopy (AFM) method. The thermodynamics parameters were investigated for corrosion of carbon steel in both the absence and presence of Schiff base.

The results of the tests showed that this compound has a good performance as an inhibitor and the percentage of inhibition on steel corrosion will increase with increasing concentration and it will reach 70% in the presence of 2 × 10⁻³ M of this inhibitor. Polarization tests indicated that this compound will act as a mixed inhibitor. Nyquist curves showed that the addition of this substance to the solution increased the charge transfer resistance and decreased the capacity of the double layer. The absorption of the new Schiff base on steel follows Langmuir adsorption isotherm, and the amount of free energy of adsorption indicates the spontaneous adsorption of this inhibitor. Using AFM investigations, the results of electrochemical methods were confirmed.

Incorporation of a new Schiff base into 1 M HCl is a promising approach for protecting the carbon steel against corrosive solution.

The purpose of this paper is to obtain a conductive polymer by using a fluorescence comonomer which is an insulator. In this study, methyl ethyl ketone formaldehyde resin (MEKFR) modified with carbazole‐9‐carbonyl chloride (CzCl) was synthesised via hydroxyl groups of MEKFR. Electrochemical polymerisation of Cz‐MEKFR comonomer was carried out potentiostatically and a green, conductive polymer P(Cz‐MEKFR) was obtained. The advantages of obtaining alternative structure of P(Cz‐MEKFR) to the random copolymer were reported.

Cz‐MEKFR comonomer was synthesised by the esterification reaction of CzCl and hydroxyl groups of MEKFR. Then, for the electrochemical polymerisation, potentiodynamic electrodeposition of Cz‐MEKFR comonomer in dichloromethane on to Pt was carried out. Electrochemical activities of polymers were tested by electrochemical methods (i.e. polarization curves and cyclovoltammetry). UV‐visible, NMR, polarization curves, cyclovoltammetric, solid‐state conductivity measurements and in situ spectroelectrochemical methods were performed for the characterization of polymers.

Carbazole‐9‐carbonyl chloride(CzCl) modified MEKFR was synthesised. This new carbazole‐modified resin (Cz‐MEKFR comonomer) has fluorescence property. The ionization potentials (Ip), electron affinity (Ea), optical band gap (Eg), peak potentials (Ep) and doping degree (y) of the polymers were calculated. Results were compared with the PCz homopolymer and the copolymer obtained from the mixture of MEKFR with carbazole P(Cz‐co‐MEKFR).

This study focuses on obtaining a conductive polymer by using a fluorescence comonomer which is an insulator. In order to remove pyridine from comonomer, successively washing with several portions of dilute aqueous H₂SO₄, water‐saturated aqueous sodium hydrogen carbonate, and hot water is necessary.

This work provides technical information for the synthesis of fluorescence comonomer and conducting an alternative polymer.

A new Cz‐CFR comonomer was synthesised. This comonomer has a higher T_m value than MEKFR alone and also has fluorescence property. The band gap of the copolymer is not remarkably lower than polycarbazole. The oxidation potential of P(Cz‐MEKFR) was found to be higher than the PCz homopolymer and the solubility of copolymer is 30 per cent higher than homopolymer.

The purpose of this paper is to conduct the synthesization of LiFePO₄-C (LFP-C) with fine particle size and enhanced electrochemical performance as the positive electrode material for Li-ion capacitors (LICs) with neutral aqueous electrolyte.

LFP-C was prepared by using polyethylene glycol (PEG) as a grain growth inhibitor, and the effects of the calcination temperature and PEG content on the structure and morphology of LFP-C were investigated. LICs using environment-friendly, safe and low-cost LiNO₃ aqueous electrolyte were assembled with LFP-C as the positive electrode and active carbon as the negative electrode. The electrochemical performances of LFP-C and LICs were studied.

The results show that the particle size of LFP-C decreases significantly through the introduction of PEG. Cyclic voltammetry results show that the LFP-C prepared at 550°C with 1.0 g PEG exhibits the highest C_pe of 725 F/g at the scanning rate of 5 mA/s. Compared to LFP prepared without PEG, the electrochemical performance of optimized LFP-C dramatically increases due to the decrease of the particle size. Moreover, the LIC assembled with the optimized LFP-C exhibits excellent electrochemical performances. The LIC maintains about 91.3 per cent of its initial C_ps after 200 cycles which shows a good cycling performance.

The LFP-C is the suitable positive electrode material for LICs with neutral aqueous electrolyte. LICs can be used in the field of automobiles and can solve the problems of energy shortage and environmental pollution.

Both the LFP-C with fine particle size and its optimal LIC using environment-friendly, safe and low-cost LiNO₃ aqueous electrolyte own good electrochemical performances.