scholarly journals Electrodeposited Ni-Fe onto Glassy Carbon for the Detection of Methylene Blue

2021 ◽  
Author(s):  
Arash Bahrololoomi ◽  
Hubert K Bilan ◽  
Elizabeth J Podlaha
Keyword(s):  
Methylene Blue ◽  
Glassy Carbon ◽  
Composite Electrode ◽  
Electrochemical Impedance ◽  
Ph Change ◽  
Nickel Iron ◽  
Ohmic Resistance ◽  
Composition Variation ◽  
Opposite Behavior ◽  
Electrodeposited Nickel

Abstract A composite electrode composed of electrodeposited, nickel-iron nanostructured clusters onto a glassy carbon (GC) disk electrode was used as a working electrode to detect methylene blue at concentrations below 10 μM. The Ni-Fe clusters were prepared by pulse electrodeposition and a lateral composition variation was observed reflective of a local pH change across the Ni-Fe feature. The applied potential for the detection of MB at a pH of 4 was determined through voltammetry and demonstrated using chronoamperometry and electrochemical impedance spectroscopy (EIS) where the adsorption of MB influenced both the capacitance, C, and ohmic resistance, Rs. A peak present in it1/2 vs t chronoamperometry plots decreased with lower MB bulk concentration, while in contrast, the RsC parameters determined from equivalent circuit models of EIS had the opposite behavior having a larger signal with lower MB concentration, and hence providing a way to increase the detection signal at lower MB concentration.

Electrochemical hydrogen peroxide sensor based on cobalt phthalocyanine captured in polyaniline film on a glassy carbon electrode

2012 ◽  
Vol 16 (04) ◽  
pp. 380-389 ◽  
Author(s):  
Berna Çeken ◽  
Mehmet Kandaz ◽  
Atıf Koca
Keyword(s):  
Hydrogen Peroxide ◽  
Glassy Carbon Electrode ◽  
Glassy Carbon ◽  
Composite Electrode ◽  
Electrochemical Impedance ◽  
Pani Film ◽  
Cobalt Phthalocyanine ◽  
Carbon Electrode ◽  
Hydrogen Peroxide Sensor ◽  
Vis Spectroscopy

This work demonstrated preparation, characterization, and application of a cobalt phthalocyanine based enzymeless/mediatorless hydrogen peroxide sensor. The cobalt phthalocyanine (CoPc) was retained in polyaniline (PANI) film on a glassy carbon electrode during electrochemical polymerization of aniline and consequently a novel composite electrode (GCE/PANI/ CoPc ) for the electrochemical sensor application was constructed. The CoPc functionalized composite electrode, GCE/PANI/ CoPc , was evaluated by voltammetry, electrochemical impedance spectroscopy, and UV-vis spectroscopy. The results displayed retaining of the CoPc molecules in the PANI film on the GCE electrode. Presence of CoPc in PANI increased conductivity of the composite on the electrode. Sensing performance of the GCE/PANI/ CoPc composite electrode to H2O2 were evaluated in detail with respect to the selectivity, reproducibility, repeatability, stability, linear concentration range, and sensitivity with voltammetric and double potential step chronoamperometric techniques. The GCE/PANI/ CoPc composite electrode gives a linear range for H2O2 between 2 and 18 μM H2O2 with sensitivities of 1.55 A.M-1 during the cathodic SWV scan and with sensitivities of 4.01 A.M-1 during the anodic SWV scan. A direct application of the sensor was performed in a real working condition, for the detection of hydrogen peroxide produced from the reaction between the glucose and glucose oxidase enzyme.

scholarly journals Sensor Based on a Poly[2-(Dimethylamino)ethyl Methacrylate-Co-Styrene], Gold Nanoparticles, and Methylene Blue-Modified Glassy Carbon Electrode for Melamine Detection

Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2850
Author(s):  
Fairouz Aberkane ◽  
Imene Abdou ◽  
Nadia Zine ◽  
Nicole Jaffrezic-Renault ◽  
Abdelhamid Elaissari ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Gold Nanoparticles ◽  
Impedance Spectroscopy ◽  
Glassy Carbon Electrode ◽  
Modified Electrode ◽  
Glassy Carbon ◽  
Electrochemical Impedance ◽  
Differential Pulse ◽  
Carbon Electrode ◽  
Detection Range

Melamine has been used as a non-protein nitrogenous additive in food products to artificially increase the apparent “false” protein content. Melamine is known as a dangerous and poisonous substance for human health and it causes diverse diseases. An electrochemical sensor for melamine detection has been developed by modification of a glassy carbon electrode using copolymer poly[DMAEMA-co-styrene], gold nanoparticles, and methylene blue. The characterization of the modified electrode was conducted using several analysis techniques including cyclic voltammetry (CV), differential pulse voltammetry (DPV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). The electrochemical detection of melamine was performed by impedance spectroscopy. Obtained results revealed that the developed sensor has a large detection range from 5.0 × 10−13 to 3.8 × 10−8 M with a low detection limit of 1.8 × 10−12 M (at S/N = 3). Various interfering species such as phenol, hydroquinone, and bisphenol A have been used and their behavior on modified electrode has been studied.

scholarly journals Optimization of Operating Conditions for Electrochemical Decolorization of Methylene Blue with Ti/α-PbO2/β-PbO2 Composite Electrode

2021 ◽  
Vol 5 (5) ◽  
pp. 117
Author(s):  
Md. Ashraful Islam Molla ◽  
Genta Yanagi ◽  
Mai Furukawa ◽  
Ikki Tateishi ◽  
Hideyuki Katsumata ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Composite Electrode ◽  
Treatment Time ◽  
Electrochemical Impedance ◽  
Cell Voltage ◽  
Operating Conditions ◽  
Optimum Operating ◽  
X Ray ◽  
Pbo2 Electrode

α-PbO2 was introduced into the intermediate layer of an electrode to prevent the separation of the electrodeposited layer and maintain oxidizing power. The resulting Ti/α-PbO2/β-PbO2 composite electrode was applied to the electrochemical decolorization of methylene blue (MB) and the operating conditions for MB decolorization with the Ti/α-PbO2/β-PbO2 electrode were optimized. The morphology, structure, composition, and electrochemical performance of Ti/α-PbO2 and Ti/α-PbO2/β-PbO2 anode were evaluated using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The optimum operating parameters for the electrochemical decolorization of MB at Ti/α-PbO2/β-PbO2 composites were as follows: Na2SO4 electrolyte 0.05 g L−1, initial concentration of MB 9 mg L−1, cell voltage 20 V, current density 0.05–0.10 A cm−2, and pH 6.0. MB dye could be completely decolorized with Ti/α-PbO2/β-PbO2 for the treatment time of less than one hour, and the dye decolorization efficiency with Ti/α-PbO2/β-PbO2 was about 5 times better, compared with those obtained with Ti/α-PbO2.

scholarly journals Electrokinetic and Impedimetric Dynamics of FeCo-Nanoparticles on Glassy Carbon Electrode

Nano Hybrids ◽  
2013 ◽  
Vol 3 ◽  
pp. 1-23 ◽  
Author(s):  
Chinwe O. Ikpo ◽  
Njagi Njomo ◽  
Kenneth I. Ozoemena ◽  
Tesfaye Waryo ◽  
Rasaq A. Olowu ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Glassy Carbon Electrode ◽  
Glassy Carbon ◽  
Transfer Process ◽  
Dimethyl Carbonate ◽  
Electrochemical Impedance ◽  
Ethylene Carbonate ◽  
Carbon Electrode ◽  
Electron Transfer Process ◽  
Feco Nanoparticles

The electrochemical dynamics of a film of FeCo nanoparticles were studied on a glassy carbon electrode (GCE). The film was found to be electroactive in 1 M LiClO4 containing 1:1 v/v ethylene carbonate dimethyl carbonate electrolyte system. Cyclic voltammetric experiments revealed a diffusion-controlled electron transfer process on the GCE/FeCo electrode surface. Further interrogation on the electrochemical properties of the FeCo nanoelectrode in an oxygen saturated 1 M LiClO4 containing 1:1 v/v ethylene-carbonate-dimethyl carbonate revealed that the nanoelectrode showed good response towards the electro-catalytic reduction of molecular oxygen with a Tafel slope of about 120 mV which is close to the theoretical 118 mV for a single electron transfer process in the rate limiting step; and a transfer coefficient (α) of 0.49. The heterogeneous rate constant of electron transfer (ket), exchange current density (io) and time constant (τ) were calculated from data obtained from electrochemical impedance spectroscopy and found to have values of 2.3 x 10-5 cm s-1, 1.6 x 10-4 A cm-2 and 2.4 x 10-4 s rad-1, respectively.

scholarly journals The effect of tamoxifen on the electrochemical behavior of Bi+3/Bi on the glassy carbon electrode and its determination via differential pulse anodic stripping voltammetry

2019 ◽  
Vol 63 (1) ◽  
Author(s):  
Mehdi Jalali ◽  
Zeinab Deris Falahieh ◽  
Mohammad Alimoradi ◽  
Jalal Albadi ◽  
Ali Niazi
Keyword(s):  
Glassy Carbon Electrode ◽  
Glassy Carbon ◽  
Electrochemical Behavior ◽  
Electrochemical Impedance ◽  
Anodic Stripping Voltammetry ◽  
Stripping Voltammetry ◽  
Differential Pulse ◽  
Peak Height ◽  
Carbon Electrode

The electrochemical behavior of Bi+3 ions on the surface of a glassy carbon electrode, in acidic media and in the presence of tamoxifen, was investigated. Cyclic voltammetry, chronoamperometry, differential pulse voltammetry, electrochemical impedance spectroscopy, and scanning electron microscopy with energy-dispersive X-ray spectroscopy were used to find the probable mechanism contributing to the reduction of the peak height of bismuth oxidation with an increase in the concentration of tamoxifen. The obtained results show a slight interaction between the bismuth species and tamoxifen which co-deposit on the surface of glassy carbon electrode. Therefore, the reduction in the peak height of bismuth oxidation as a function of tamoxifen concentration was used to develop a new differential pulse anodic striping voltammetry method for determination of trace amount of tamoxifen. The effects of experimental parameters on the in situ DPASV of Bi+3 ions in the presence of tamoxifen shown the optimal conditions as: 2 mol L-1 H2SO4 (1% v v-1 MeOH), a deposition potential of -0.5 V, a deposition time of 60 s, and a glassy carbon electrode rotation rate of 300 rpm. The calibration curve was plotted in the range of 0.5 to 6 µg mL-1 and the limits of detection and quantitation were calculated to be 3.1 × 10-5 µg mL-1 and 1.0 × 10-4 µg mL-1, respectively. The mean, RSD, and relative bias for 0.5 µg mL-1 (n=5) were found to be 0.49 µg mL-1, 0.3%, and 2%, respectively. Finally, the proposed method was successfully used for the determination of tamoxifen in serum and pharmaceutical samples.

scholarly journals Cellulose microfibers (CMFs) reinforced smart self-healing polymeric composite coatings for corrosion protection of steel

2020 ◽  
Author(s):  
Muddasir Nawaz ◽  
Sehrish Habib ◽  
Adnan Khan ◽  
Abdul Shakoor ◽  
Ramazan Kahraman
Keyword(s):  
Corrosion Resistance ◽  
Immersion Time ◽  
Electrochemical Impedance ◽  
Composite Coatings ◽  
Polymeric Composite ◽  
Protective Film ◽  
Self Healing ◽  
Ph Change ◽  
Smart Coatings ◽  
Cellulose Microfibers

The use of organic coating for the metals has been widely being used to protect the surface against corrosion. Polymeric coating incorporated with Nanocontainers loaded with inhibitor and self-healing provides better corrosion resistance. Cellulose microfibers (CMFs) used as smart carriers were synthesized and loaded with dodecylamine (DOC)-inhibitor and polyethyleneimine (PEI)-both inhibitor and self-healing agents. Smart polymeric coatings were developed by mixing CMF/DOC and CMFs/PEI into the epoxy matrix. Reference coatings (that has only CMFs) were also prepared for a compersion. Scanning electron microscope (SEM), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR) and thermal gravitational analysis (TGA) were used to confirm the loading of DOC and PEI onto the CMFs. UV-vis analysis indicates that the self-release of inhibitor from CMFs is sensitive to pH of the solution and the immersion time. Recovery of controlled surface damage confirms the decent self-healing ability of the prepared smart coatings is due to the efficient release of inhibitor (DOC) and self-healing agent (PEI) in the damaged area leading to the formation of a protective film. Electrochemical impedance spectroscopy (EIS) results demonstrate that corrosion resistance of the smart coating increases with an increase in immersion time which is due to the progressive release of inhibitors from CMFs in response to the pH change. Therefore, smart coatings demonstrate superior properties as compared to the reference coatings. The study reveals the polymeric composite coatings have potential to inhibit the corrosion of steel for oil and gas industry.

Sign in / Sign up

Export Citation Format

Share Document