Carbon Ceramic Electrode Research Articles

Kinetics of ethylene glycol electrooxidation on the noble metal-based nano-catalysts

A comparative electrooxidation of Eg in the alkaline solution was investigated over Pt, Pd and Au nanoparticle-modified carbon-ceramic electrode. The kinetic parameters of Eg oxidation, i.e., Tafel slope and activation energy (E a), were determined on the modified electrodes. The lowest E a value of 8.9 kJ mol−1 was calculated on Pt|CCE. In continuation, the reaction orders with respect to the Eg and NaOH concentrations on Pd|CCE were found to be 0.4–0.2 and 0.6, respectively. An adsorption equilibrium constant (b) of 22.36 M−1 and the adsorption Gibbs energy change (ΔG°) of −7.7 kJ mol−1 were obtained on Pd|CCE. The chronopotentiometry (CP) and chronoamperometry (CA) results showed that Pd|CCE and then Au|CCE have better performance stability than Pt|CCE for Eg electrooxidation. Additionally, the electrochemical impedance spectroscopy (EIS) suggested faster electron-transfer kinetics on Pt than that on the Pd and Au electrocatalysts.

A novel electrochemical cyanide sensor using gold nanoparticles decorated carbon ceramic electrode

The high toxicity of cyanide and its great variety of uses in industrial processes make it necessary to develop sensitive and selective sensors for its determination in natural and waste waters. In this work, using modified carbon ceramic electrode with gold nanoparticles (GNPs) was reported. The electrodeposition of GNPs on carbon ceramic electrode (CCE) was confirmed by scanning electron microscopy (SEM). The SEM image showed that the size of gold nanoparticles was examined around 75nm. The GNPs/CCE was used for the determination of cyanide (CN−) in solution (pH12). The cyclic voltammetry (CV) and square wave voltammetry (SWV) methods were used for the determination of CN−. The linear dynamic range from 0.5μM to 14.0μM and a detection limit was found to be 0.09μM (S/N=3) by SWV method. Interference studies were performed with typical anions present in natural and waste waters. Based on obtained result, the proposed sensor suffers from the interfering of thiocyanide (SCN−) ion.

NiO nanoparticles electrodeposited on reduced GO–CuO nanocomposite bulk modified CCE as a sensitive glucose sensor

A novel enzymeless glucose sensor based on nickel oxide (NiO) nanoparticles electrodeposited on reduced graphene oxide-copper oxide nanocomposite bulk modified carbon ceramic electrode (rGO-CuO/CCE) was reported. The prepared NiO/rGO-CuO/CCE was characterised by scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic-force microscopy, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry techniques. Electrocatalytic performance of the NiO/rGO-CuO/CCE was investigated in details for the electro-oxidation of glucose using cyclic voltammetry and amperometry techniques. The developed sensor responds efficiently to glucose over the concentration range 5-920 μM with the detection limit 2.63 μM and sensitivity 5980 μA mM -1 cm -2 . According to EIS studies, ternary presence of rGO, CuO and NiO nanoparticles increased the electron transfer performance and sensitivity of NiO/rGO-CuO/CCE to glucose. The prepared sensor was applied for the determination of glucose in human serum samples with satisfactory results. Owing to renewable and polishable surface, high sensitivity, reproducible responses and long-term stability, the developed sensor could be used in clinical applications.

Synthesis of fullerene (C60-monoadduct)-based water-compatible imprinted micelles for electrochemical determination of chlorambucil

A novel water-compatible C60-monoadduct based imprinted micelles was synthesized by the self-assembly of vinylic-C60-monoadduct with sodium dodecylsulfate micellar system, in the presence of chlorambucil as a model template (anticancer drug). After template retrieval with acetonitrile, these imprinted micelles were immobilized at the surface of ionic liquid decorated carbon ceramic electrode. Herein, C60-monoadduct (the head group of micelle) actually served as a nanomediator for electronic transmission across multiple interfaces. Such modification induced electrocatalytic characteristics by decreasing analyte oxidation overpotential and thereby augmented the electrode kinetics. Consequently, the differential pulse anodic stripping transduction was realized to be approximately four-fold as compared to the corresponding electrode modified without C60-monoadduct. This revealed the potential role of fullerene as nanomediator in the signal transduction. Herein, ionic liquids facilitated electron transport by two-fold without any interfacial barrier through carbon layers than that realized with modified ceramic electrodes made in the absence of ionic liquids. A perfect linearity in the current-concentration profile under optimal conditions was observed for the analyte concentration in the range 1.47–247.20ngmL-1, with the detection limits to the tune of 0.36ngmL-1 (S/N=3) in aqueous and real samples.

High-sensitive amperometric hydrazine sensor based on chemically synthesized zinc nitroprusside nanoparticle-supported carbon ceramic electrode

Zinc nitroprusside (ZnNP) nanoparticles were fabricated at the surface of zinc powder-doped carbon ceramic electrode (CCE) by a chemical derivatization process. This modified electrode was characterized by scanning electron microscopy, atomic force microscopy and cyclic voltammetry techniques. The charge transfer rate constant (ks) and charge transfer coefficient (α) were calculated for the electron exchange reaction of the ZnNP thin film. The ZnNP nanoparticle-modified CCE (ZnNP|CCE) showed good electrocatalytic activity toward hydrazine oxidation. The limit of detection (S/N = 3) and sensitivity were found to be 0.16 µM and 0.21 µA/µM, respectively. The mechanism of hydrazine electrooxidation at the electrode surface was studied. Finally, the ZnNP|CCE was successfully used for the determination of trace amount of hydrazine in different spiked and real samples.

Fabrication and Application of Ferrierite–Modified Carbon Ceramic Electrode in Sensitive Determination of Estradiol

The preparation and characterization of entire volume modified carbon ceramic electrode (CCE) produced by the sol-gel method was reported. For the first time, this type of electrode was modified using ferrierite (FER) belonging to zeolites. The morphology and topography of FER–modified CCE were analyzed using scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. The electrochemical behavior of FER-CCE in presence of estradiol was tested via cyclic voltammetry. Moreover, the differential pulse voltammetric (DPV) procedure for determination of estradiol was developed. For the comparison the bare ceramic electrode (GP-CCE) was also prepared and investigated in analogous way. The introduction of ferrierite into carbon-ceramic matrix influenced the surface properties and analytical performance of fabricated CCE. The electrode with FER possessed better analytical properties - lower limit of detection (LOD) and lower limit of quantification (LOQ) in comparison to bare electrode. Additionally, the estimated linear dynamic range (LDR) showed better usability of FER-CCE for determination of lower amount of estradiol, since LDR was 0.2–30 μmol L−1 and 4–40 μmol L−1 for FER-CCE and GP-CCE, respectively. Finally, the developed FER-CCE and DPV procedure were successfully used to determine estradiol in pharmaceutical sample–Estrofem tablets.

Electrochemical Characterization of a Carbon Ceramic Electrode Modified with a Ru(II) Arene Complex and Its Application as Voltammetric Sensor for Paracetamol

An arene-ruthenium (II) complex - [Ru(η6-p-cymene)(ampy)Cl]PF6, where ampy is 2-(aminomethyl)pyridine - was synthesized and used in the construction of a modified carbon ceramic electrode (Ru-CCE) for determining paracetamol (PCT) by square wave voltammetry (SWV). The modified electrode, constructed by sol–gel methods, provides a considerable enhancement of PCT oxidation. Under the optimized working conditions, the peak current is linear to the PCT concentration in the ranges of 1.99 × 10−6–3.10 × 10−5 mol L−1 with a detection limit of 5.83 × 10−7 mol L−1. The Ru-CCE showed good repeatability and reproducibility (RSD < 4%), long-term stability (>12 months). Lastly, the proposed sensor was used for the determination of PCT in pharmaceutical formulations, offering a promising tool for quality control.

Amperometric NADH sensor based on a carbon ceramic electrode modified with the natural carotenoid crocin and multi-walled carbon nanotubes

A carbon ceramic electrode (CCE) was fabricated from a composite consisting of sol-gel, ceramic graphite, multi-walled carbon nanotubes and the natural carotenoid crocin. The resulting sensor is shown to allow for the determination of NADH at a rather low working potential of 0.22 V (vs. Ag/AgCl). The heterogeneous electron transfer rate constant (ks) and the surface coverage of the modified electrode are 16.8 s−1 and 22 pmol·cm−2, respectively. The sensor shows excellent and linear response in solutions of pH 7.0 over the 0.5 to 100 μM NADH concentration range, a 0.1 μM detection limit, and a sensitivity of 251.3 nA·μM−1·cm−2.

Electrooxidation of Formic Acid and Formaldehyde on the Fe3O4@Pt Core-Shell Nanoparticles/Carbon-Ceramic Electrode

In the present work, the electrooxidation of formic acid and formaldehyde; potentially important fuels for future fuel cells, was investigated on the Fe3O4@Pt core-shell nanoparticles/carbon-ceramic electrode (Fe3O4@Pt/CCE). The Fe3O4@Pt nanoparticles were prepared via a simple and fast chemical method and their surface morphology, nanostructure properties, chemical composition, crystal phase, and electrochemical behavior were investigated by scanning electron microscope, transmission electron microscope, X-ray diffraction, energy dispersive X-ray spectroscopy and electrochemical methods, respectively. Then the electrocatalytic activity of the Fe3O4@Pt/CCE toward the oxidation of formic acid and formaldehyde was studied in details. The primary electrochemical analysis shows that the Fe3O4@Pt/CCE has superior catalytic activity and stability for formic acid and formaldehyde oxidation compared to Pt-alone nanoparticles on the carbon-ceramic electrode (Pt/CCE). The present investigation demonstrates that the Fe3O4@Pt/CCE electrocatalyst may play a significant role in future fuel cell applications.

A Renewable and Sensitive Glucose Sensor Based on Bulk-Modified Reduced Graphene Oxide-Nickel Oxide Nanocomposite Carbon Ceramic Electrode

A Renewable and Sensitive Glucose Sensor Based on Bulk-Modified Reduced Graphene Oxide-Nickel Oxide Nanocomposite Carbon Ceramic Electrode

Ionic liquid modified carbon-ceramic electrode with structure similar to Graphene nanoplatelets: Application to Imidacloprid determination in some agricultural products

Abstract 1-Allyl-3-methylimidazolium tetraflouroborate ([AMIM][BF 4 ]) ionic liquid modified carbon-ceramic electrode was applied for Imidacloprid electrochemical determination. Surface of the modified electrode was characterized using s canning electron microscopy (SEM), and Energy Dispersive X-ray Analysis (EDX). These analyses showed the deposition of ionic liquid on the surface of carbon-ceramic electrode caused formation of graphene-like nanoplatelets. Based on high surface area and rich edge defects which resulting from graphene-like nanoplatelets and high ionic conductivity of ionic liquid (IL), the modified electrode exhibited electro-catalytic activity for Imidacloprid reduction. Operational parameters including IL volume, solution pH; which affect the analytical performance of modified electrode were optimized. The calibration curve for Imidaclopride was linear in the range of 5 × 10 −8 –7 × 10 −6 M with the detection limit (S/N = 3) of 31 nM (3.1 × 10 −8 M). This modified electrode was applied for imidacloprid determination in some commercial formulation and agricultural products and the results were in good agreement with standard high-performance liquid chromatography method.

The effect of carbon material on the electroanalytical determination of 4-chloro-3-methylphenol using the sol-gel derived carbon ceramic electrodes

A surface renewable ceramic electrode modified in its entire volume with multi-walled carbon nanotubes (CNT-CCE) was obtained by the sol-gel method. Bare carbon ceramic electrode (GP-CCE) was also produced for comparison. The surface morphology and electrochemical properties of the electrodes were analyzed. The morphology and topography were tested by means of, respectively, scanning electron microscopy (SEM) and atomic force microscopy (AFM). Cyclic voltammetry was used to analyze the electrochemical features (e.g. potential window). Moreover, the obtained electrodes were used for square wave voltammetric (SWV) determination of 4-chloro-3-methylphenol (PCMC). The calibration curves were obtained for GP-CCE and CNT-CCE in the chosen optimal experimental conditions (composition of the supporting electrolyte, step potential, amplitude, frequency). The concentration ranges of 9–29μmolL−1 and 3–32μmolL−1 were recorded, respectively, for GP-CCE and CNT-CCE. The proposed method was validated, and the limit of detection (LOD) and the limit of quantitation (LOQ) were calculated. Finally, the obtained electrodes and the developed procedure were successfully applied to determine PCMC in spiked tap water. Satisfactory results were obtained, and they demonstrated that using MWCNTs instead of GP improves the quality of the CCE electrodes.

Graphene nanoplatelets like structures formed on ionic liquid modified carbon-ceramic electrode: As a sensing platform for simultaneous determination of dopamine and acetaminophen

Room temperature ionic liquid as 1-allyl-3-methylimidazolium tetraflouroborate ([AMIM][BF4]) was used for surface modification of carbon-ceramic electrode. The surface of the modified electrode was characterized using scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM) and Raman spectroscopy. Based on these studies we were concluded that deposition of ionic liquid on the carbon-ceramic electrode surface caused the formation of graphene nanoplatelets like structures on its surface.This modified electrode was used for simultaneous electrochemical determination of dopamine (DA) and acetaminophen (AP). Because of effective separation of oxidation peak potentials of DA and AP on modified electrode, simultaneous determination of them was possible. Operational parameters such as amount of IL volume, solution pH, scan rate; which affected the analytical performance of modified electrode were optimized. The calibration curves for DA and AP were linear in the range of 0.1–20μM and 0.1–20μM with the detection limit (S/N=3) of 68nM and 63nM, respectively. The high repeatability, reproducibility, and long-term life time were of modified electrode figure of merits. The present electrode was successfully applied for the determination of DA and AP in some commercial pharmaceutical samples, human blood serum, and urine samples with satisfactory results.

Maternal KIR-B haplotype in combination with fetal HLA-C2 is associated with pregnancy acute atherosis in the decidua basalis

Room temperature ionic liquid as 1-allyl-3-methylimidazolium tetraflouroborate ([AMIM][BF4]) was used for surface modification of carbon-ceramic electrode. The surface of the modified electrode was characterized using scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM) and Raman spectroscopy. Based on these studies we were concluded that deposition of ionic liquid on the carbon-ceramic electrode surface caused the formation of graphene nanoplatelets like structures on its surface.This modified electrode was used for simultaneous electrochemical determination of dopamine (DA) and acetaminophen (AP). Because of effective separation of oxidation peak potentials of DA and AP on modified electrode, simultaneous determination of them was possible. Operational parameters such as amount of IL volume, solution pH, scan rate; which affected the analytical performance of modified electrode were optimized. The calibration curves for DA and AP were linear in the range of 0.1–20 μM and 0.1–20 μM with the detection limit (S/N = 3) of 68 nM and 63 nM, respectively. The high repeatability, reproducibility, and long-term life time were of modified electrode figure of merits. The present electrode was successfully applied for the determination of DA and AP in some commercial pharmaceutical samples, human blood serum, and urine samples with satisfactory results.

Fabrication of ferrocene functionalised ionic liquid/carbon nanotube nanocomposite modified carbon-ceramic electrode: application to the determination of hydrazine

ABSTRACTA novel ionic liquid, 1-(ferrocenyl butyl)-3-methylimidazolium tetrafluoroborate (Fc-IL), was synthesised. The nanocomposite of Fc-IL and multi-walled carbon nanotubes (MWCNTs) was constructed and used for surface modification of carbon-ceramic electrode. The modified electrode was applied to the determination of hydrazine. Operational parameters such as pH of the solution, ionic liquid volume and amount of carbon nanotubes, which affect the analytical performance of the modified electrode, were optimised. The linear range of the modified electrode toward hydrazine concentration was 0.96–106.10 μg L–1 with a detection limit of 0.64 μg L–1 (S/N = 3). The modified electrode displayed high repeatability, reproducibility, long-term life time and low response time (<3 s). The applicability of this method was further tested by analysing the hydrazine content in boiler-feed water samples containing different concentrations of hydrazine and the results were in good agreement with the spectrophotometry method.

Electrooxidation of glycerol on nickel and nickel alloy (Ni–Cu and Ni–Co) nanoparticles in alkaline media

In the present study, nickel (Ni) and Ni alloy (Ni–Cu and Ni–Co) nanoparticles modified carbon-ceramic electrodes (Ni/CCE, Ni–Cu/CCE and Ni–Co/CCE) were prepared by an electrochemical process for the oxidation of glycerol.

Flow injection amperometric detection of insulin at cobalt hydroxide nanoparticles modified carbon ceramic electrode

Cobalt hydroxide nanoparticles were prepared onto a carbon ceramic electrode (CHN|CCE) using the cyclic voltammetry (CV) technique. The modified electrode was characterized by X-ray diffraction and scanning electron microscopy. The results showed that CHN with a single-layer structure was uniformly electrodeposited on the surface of CCE. The electrocatalytic activity of the modified electrode toward the oxidation of insulin was studied by CV. CHN|CCE was also used in a homemade flow injection analysis system for insulin determination. The limit of detection (signal/noise [S/N] = 3) and sensitivity were found to be 0.11 nM and 11.8 nA/nM, respectively. Moreover, the sensor was used for detection of insulin in human serum samples. This sensor showed attractive properties such as high stability, reproducibility, and high selectivity.

Surface decoration of Au–Pt bimetallic inorganic–organic hybrid nanocomposite modified carbon ceramic electrode with vanadium N-salicylidene-L-histidine–al-MCM-41 for electrooxidation of thiosulphate

This work describes the electrochemical behavior of vanadium N-salicylidene-L-histidine-Al-mobil composition of matter no. 41 (MCM-41) (V(His)/Al-MCM-41) film immobilized on the surface of bimetallic Au–Pt inorganic–organic hybrid nanocomposite carbon ceramic electrode and its electrocatalytic activity toward the oxidation of thiosulphate. The surface structure and composition of the sensor was characterized by scanning electron microscopy (SEM). Electrocatalytic oxidation of thiosulphate on the surface of modified electrode was investigated with cyclic voltammetry, chronoamperometry and hydrodynamic amperometric techniques and the results showed that the vanadium film displays excellent electrochemical catalytic activities towards thiosulphate oxidation. The modified electrode indicated reproducible behavior and high level of stability during the electrochemical experiments.

Application of multi wall carbon nanotube–graphene hybrid for voltammetric determination of naproxen

This work describes the synthesis of multi wall carbon nanotube–graphene hybrid and its application to electrochemical determination of naproxen. The surface of fabricated hybrid was studied using field emission scanning electron microscopy (FESEM), Fourier transform infrared (FT-IR), and X-ray diffraction (XRD) techniques. A carbon ceramic electrode modified with multi wall carbon nanotube–graphene–ionic liquid nanocomposite films exhibits an excellent effect on the electrochemical oxidation of naproxen compared with a bare carbon ceramic electrode. The measurements were carried out using differential pulse voltammetry (DPV) and cyclic voltammetry (CV), based on the experiment outcomes a possible mechanism for oxidation of naproxen was proposed and discussed. The modified electrode was found to exhibit a linear response over concentration range of 8 × 10−7–10−4 mol L−1 with a detection limit of 1.25 × 10−7 mol L−1 and sensitivity of 0.3533 µA µM−1 under the optimized conditions. The developed sensor was applied for determination of naproxen in human blood plasma.

Palladium nanoparticles/nanostructured carbon black composite on carbon–ceramic electrode as an electrocatalyst for formic acid fuel cells

Palladium nanoparticles/nanostructured carbon black composite (PdNPs/NCB), supported on the carbon–ceramic electrode (CCE), has been prepared by a chemical reduction method using sodium borohydride as a reducing agent. The synthesized composite was characterized by scanning electron microscopy, high resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and electrochemical methods to delineate its surface morphology, nanostructure properties, composition, crystal phases and electrochemical properties. The obtained modified electrode, PdNPs/NCB/CCE, was used as an efficient electrocatalyst for the oxidation of formic acid. Electrochemical techniques including cyclic voltammetry and chronoamperometry were applied for electrocatalytic investigations and it was found that the PdNPs/NCB/CCE was catalytically more active than the Pd nanoparticles supported on the CCE without NCB (PdNPs/CCE). The effect of some experimental factors was studied and optimum conditions were suggested. The obtained results show that the PdNPs/NCB/CCE has satisfactory stability and reproducibility for electrooxidation of formic acid when stored in ambient conditions and improved electrocatalytic activity in continued cycling which make it more attractive for formic acid fuel cell applications.