| 1. |
- Amin, Muhammad, 1979, et al.
(author)
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Coin-cell Supercapacitors Based on CVD Grown and Vertically Aligned Carbon Nanofibers (VACNFs)
- 2017
-
In: International Journal of Electrochemical Science. - : Elsevier BV. - 1452-3981. ; 12:7, s. 6653-6661
-
Journal article (peer-reviewed)abstract
- Complete supercapacitors (SCs) comprising vertically aligned carbon nanofibers (VACNFs) as electrode materials have been assembled as coin-cells. The VACNFs were grown directly onto the current collector by direct current plasma enhanced chemical vapor deposition (DC-PECVD), thereby providing excellent contact with the current collector, but also eliminating the need of any binder. The vertical alignment facilitates fast ion transport and the electrolyte to access the entire surface of the CNFs. The morphology of the VACNFs was evaluated by scanning electron microscopy (SEM), while the performance was assessed by several methods: cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and device related cycling by galvanostatic charge/discharge. The capacitance, 3.64 mF/cm2 , is >15 times higher than the capacitance of a coin-cell without CNFs and the cyclic performance shows these proof-of-concept SCs to retain >80% of the capacitance after 2000 full charge/discharge cycles. The direct growth of VACNFs as electrodes at the current collector opens pathways for SC production using existing coin-cell battery production technology.
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| 2. |
- Bettini, Eleonora, et al.
(author)
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Nature of current increase for a CoCrMo alloy : "transpassive" dissolution vs. water oxidation
- 2013
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 8:10, s. 11791-11804
-
Journal article (peer-reviewed)abstract
- The “transpassive” behavior of a CoCrMo alloy has been investigated to clarify the nature of the current increase at high anodic potential (0.5-0.7 VAg/AgCl). The total amount of released metal ions was determined after the potentiostatic measurements. According to the calculation through Faradays’ law, the metal dissolution only contributes to part of the total current recorded. Electrochemical AFM mapping did not show pronounced topography changes at 0.65 VAg/AgCl, while light optical microscopy observation revealed fast evolution of oxygen bubbles. Evidently water oxidation is another important process largely contributing to the current increase at the high potential.
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| 3. |
- Bettini, Eleonora, et al.
(author)
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Study of Corrosion Behavior of a 2507 Super Duplex Stainless Steel : Influence of Quenched-in and Isothermal Nitrides
- 2014
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 9:1, s. 61-80
-
Journal article (peer-reviewed)abstract
- Precipitation of different types of chromium nitrides may occur during processing of super duplex stainless steels, affecting the properties of the material. In this study the influence of quenched-in (size range ca. 50-100 nm) and isothermal (size range ca. 80-250 nm) types of nitrides on the corrosion behavior of a 2507 super duplex stainless steel has been investigated at room temperature and at 90 degrees C (above the critical pitting temperature) in 1 M NaCl solution. The microstructure has been characterized by scanning electron microscopy and magnetic force microscopy. The isothermal nitrides exhibit a higher Volta potential compared to the matrix, but such difference could not be observed for the quenched-in nitrides. In-situ electrochemical AFM measurements at room temperature show stable surfaces for a wide range of applied potentials despite the presence of either type of nitrides. In the transpassive region isothermal nitrides appear to be slightly more deleterious than quenched-in nitrides. At 90 degrees C isothermal nitrides largely reduce the corrosion resistance of the austenite phase, while the quenched-in nitrides reduce the corrosion resistance of the material to a much lesser extent. The size difference between isothermal and quenched-in chromium nitrides may be crucial, in particular above the critical pitting temperature.
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| 4. |
- El-Kemary, Maged, et al.
(author)
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Calendula officinalis-mediated biosynthesis of Silver Nanoparticles and their Electrochemical and Optical Characterization
- 2016
-
In: International Journal of Electrochemical Science. - : Elsevier BV. - 1452-3981. ; 11:12, s. 10795-10805
-
Journal article (peer-reviewed)abstract
- The metal nanoparticles synthesis is highly explored field of nanotechnology. The biological methods seem to be more effective. A simple and elegant method is adopted to prepare Silver nanoparticles (AgNPs) in a single step using Calendula officinalis extract (COE) as reducing and stabilizing agent. The plant extract is mixed with AgNO3 to get biosynthesized AgNPs. The biosynthesized AgNPs were both optically and electrochemically characterized by UV-Vis, Infrared spectroscopy, Transmission Electron Microscopy, Fluorescence spectroscopy, Zeta potential and Cyclic Voltammetry. The results showed Calendula officinalis extract is a useful bioreductant for the synthesis of AgNPs. This study infers that the size of biosynthesized AgNPs ranges from 30 to 50 nm. The surface plasmon resonance peak in the UV-Vis absorption spectra shows maximum absorption at 435 nm. Fluorescence spectra of silver nanoparticles, which show an emission peak at 468 nm have also been studied. Zeta potential analysis ensured the biosynthesized AgNPs are highly stable. Using this environmentally friendly method of biological AgNPs production supplies rates of biosynthesis facile in comparison with other chemical and engineered routes. The employment of traditional medicine in biosynthesis protocols can potentially open new doors in various human health and well-being implications such as cosmetics, foods and medicine.
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| 5. |
- Fan, Liangdong, et al.
(author)
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Proton and Oxygen Ionic Conductivity of Doped Ceria-Carbonate Composite by Modified Wagner Polarization
- 2012
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 7:9, s. 8420-8435
-
Journal article (peer-reviewed)abstract
- The impressive ionic conductivity and tunable conduction behaviors have made the ceria-carbonate composite an attractive electrolyte for low temperature ceramic fuel cells. However, the conduction mechanism is not yet well studied. In the present study, both proton and oxygen ion conductivity as well as the transport properties of samaria-doped ceria/ sodium-lithium-carbonate (denoted as SDCLN) composite are investigated by the fuel cell study and the modified Hebb-Wagner polarization measurements. The multi-ionic polarization behaviors and the transfer processes in composite electrolyte under external electrical field are analyzed. A maximum power density of 780 mW cm(-2) and a calculated total ion (proton and oxygen ion) conductivity of 0.153 S cm(-1) are obtained under H-2/air condition at 550 degrees C. The Wagner DC polarization measurements show that the proton conduction dominates the total ionic conductivity. A synergistic effect exists between the charge carriers in the doped ceria-carbonate composite system. An ideal interfacial conduction model is also proposed based on the obtained results.
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| 6. |
- Fathy, Marwa, et al.
(author)
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Quasi-solid-state Electrolyte for Dye Sensitized Solar Cells Based on Nanofiber PMA-PVDF and PMA-PVDF/PEG Membranes
- 2016
-
In: International Journal of Electrochemical Science. - : Elsevier BV. - 1452-3981. ; 11:7, s. 6064-6077
-
Journal article (peer-reviewed)abstract
- Novel electrospun membranes quasi-solid electrolytes based on blends of polymethylacrylate (PMA) - polyvinylidene fluoride (PVDF), and PMA-PVDF/PEG (polyethylene glycol) are prepared by electrospinning technique and applied as quasi-solid state electrolytes in dye sensitized solar cells (DSSCs). The membranes are characterized by Fourier transform infrared (FT-IR) spectrophotometer, differential scanning calorimeter (DSC), Scanning electron microscopy (SEM), and Electrochemical impedance spectroscopy. The crystallinity obtained from the DSC data increased with the increase of PVDF wt% in PMA-PVDF blend and then decreased for the PMA-PVDF/PEG membranes. The fully interconnected porous structure of the host polymer membranes of PMA-PVDF (4: 6 wt%) exhibited a high electrolyte uptake reached to similar to 265% and an ionic conductivity of 2.1x10(-3) S cm(-1), which is increased to 406.3%, and 3.2 x 10(-3) S cm(-1), respectively for PMA-PVDF/PEG (4: 6: 4 wt%) membrane. DSSC is assembled by PMA-PVDF(4: 6 wt%) and attained an overall energy conversion efficiency of 6.6% at light intensity of 100 mW cm(-2). The presence of 4 w% PEG in the electrolyte membrane increased the energy conversion efficiency to 7 % giving a promise candidate for scaling up this type of DSSCs.
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| 7. |
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| 8. |
- Fragkou, Vasiliki, et al.
(author)
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Determination of the Real Surface Area of a Screen-Printed Electrode by Chronocoulometry
- 2012
-
In: International Journal of Electrochemical Science. - : ELECTROCHEMICAL SCIENCE GROUP, A SPOMENICE 7/12 , 19210 BOR, BELGRADE, VJ 12, SERBIA. - 1452-3981. ; 7:7, s. 6214-6220
-
Journal article (peer-reviewed)abstract
- A simple and effective method applying chronocoulometry and cyclic voltammetry to the determination of the real surface area of a screen-printed electrode, for the first time, is reported. The method is based on the Anson plot and the standard addition method. This method could greatly facilitate determination of the real surface area of commercial screen-printed electrodes, which still remains underdeveloped despite the critical importance of quality control in this industry.
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| 9. |
- Hedberg, Yolanda, et al.
(author)
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Influence of Surface Oxide Characteristics and Speciation on Corrosion, Electrochemical Properties and Metal Release of Atomized 316L Stainless Steel Powders
- 2012
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 7:12, s. 11655-11677
-
Journal article (peer-reviewed)abstract
- Surface oxide characteristics of powder particles are important to consider for any toxicological risk assessment based on in-vitro or in-vivo tests. This study focuses on a multi-analytical approach (X-ray photoelectron spectroscopy, Auger electron spectroscopy, scanning- and transmission electron microscopy, and different electrochemical techniques) for in-depth characterization of surface oxides of inert-gas-atomized (GA) AISI 316L stainless steel powder, compared with massive sheet and a water-atomized (WA) 316L powder. Implications of differences in surface oxide phases and their surface distribution on corrosion, electrochemical properties and metal release are systematically discussed. Cr was enriched in an inner surface layer for both GA powders, with Mn and S enriched in the outermost surface oxide. The surface oxide was 2-5 nm thick for both GA powder size fractions, amorphous for the GA powder sized <4 μm and partially crystalline for the powder sized <45 μm. A strong ennoblement, i.e. positive shift in open circuit potential, of up to 800 mV, depending on solution, was observed for the GA powders. This ennoblement was induced by catalytic oxygen reduction properties of tri- or tetravalent Mn-oxides, not present on the massive sheet or WA powder. In contrast to the predominant presence of a trivalent Cr-oxide in the surface oxide of the GA powder particles, the WA<45μm powder revealed oxidized Cr, most probably present in its hexavalent state (not chromate), within a silicate-rich surface oxide. This study clearly shows that the surface oxide composition and speciation of differently sized GA and WA powders are unique (strongly connected to the atomization process) and of large importance for their pitting corrosion and metal release properties. For the GA<45μm powder, Mn-rich oxide nanoparticles were proposed to account for its higher pitting corrosion susceptibility, a more stable surface ennoblement, and a shift of the MnO2 oxidation/reduction peaks in the cyclic voltammogram, compared with the GA particles sized <4μm. The thermodynamically unstable ferritic structure of the small sized particle fraction (GA <4μm), despite an austenitic composition, revealed a higher pitting corrosion susceptibility and higher nickel release compared with the austenitic particle fraction of the GA <45 μm powder.
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| 10. |
- Hedberg, Yolanda, et al.
(author)
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Micro-Capillary Electrochemical and Microscopic Investigations of Massive and Individual Micrometer-Sized Powder Particles of Stainless Steel 316L
- 2012
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 7:12, s. 11678-11695
-
Journal article (peer-reviewed)abstract
- Material properties, corrosion, and metal release from stainless steel powders are important factors to assess any occupational health hazards. This paper elucidates the corrosion behavior of stainless steel particles (inert-gas-atomized AISI 316L powders sized < 45μm, polished and non-polished) compared with corresponding massive low-sulfur bulk sheet material. Electrochemical measurements using a microcapillary technique are compared with ex-situ optical and scanning electron microscopy imaging and electron dispersive X-ray spectroscopy elemental analysis on the same area of individual particles. Non-polished 316L particles were significantly more passive compared to polished massive sheet and polished particles that in general showed a similar corrosion behavior. Corrosion was not induced by bulk compositional differences but could be attributed to surface inhomogeneities. The results are in agreement with the high passivity of non-polished particles in macroscopic studies, an effect caused by an unique surface oxide, characterized in part I of this paper series.
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| 11. |
- Hu, Jinghua, et al.
(author)
-
Synthesis and First-principle Calculation of TiO2 Rutile Nanowire Electrodes for Dye-sensitized Solar Cells
- 2017
-
In: International Journal of Electrochemical Science. - : Electrochemical Science Group. - 1452-3981. ; 12:10, s. 9725-9735
-
Journal article (peer-reviewed)abstract
- In this paper, a TiO2 nanowire film synthesized via a hydrothermal method was prepared as a photoanode for dye-sensitized solar cells (DSSCs). The synthesized TiO2 nanowires were characterized by transmission electron microscopy and X-ray diffraction. The TiO2 nanowire film greatly improved the efficiency of the DSSC owing to the rapid interfacial electron transport in the one-dimensional TiO2 nanowires. The light absorption and interfacial electron transport, which play important roles in the efficiency of DSSCs, were investigated by UV-vis absorption spectroscopy and electrochemical impedance spectroscopy. The energy band structure and electron density of states of the rutile nanowire were calculated using a first-principles method and compared to bulk anatase and rutile TiO2 phases. The band gap of the rutile TiO2 nanowire was found to be less than that of anatase TiO2 by 0.6 eV. Further calculations using GGA+U yielded a similar band gap reduction. In addition to the redshift of the absorption edge originating from the smaller band gap, the larger surface area of the TiO2 nanowire compared to the bulk material is expected to facilitate the migration of photogenerated electrons and holes from inside to the surface of the material. This would result in a considerable improvement of the photocatalytic efficiency of TiO2.
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| 12. |
- Jukka-Pekka, Spets, et al.
(author)
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Test of Different Anode Electrocatalysts for Direct Glucose Anion Exchange Membrane Fuel Cell
- 2016
-
In: International Journal of Electrochemical Science. - : Electrochemical Science Group. - 1452-3981. ; 11:6, s. 4219-4230
-
Journal article (peer-reviewed)abstract
- Direct glucose anion exchange membrane fuel cell (AEMFC) with near-neutral-state electrolyte of 0.1 M [PO4] (tot) was studied with five different anode electrocatalysts (Pt, PtRu, PtNi, Au, PdAu) at a temperature of 37 degrees C and at a glucose concentration of 0.1 M. The cathode catalyst in each test was Pt supported on carbon (60 wt.%). Four anode electrocatalysts (supported on carbon) had a total metal content of 40 wt.% while the fifth anode material of PtRu had a higher content of 60 wt.%. Moreover, in order to show the influence of the metallic content on the fuel cell performance, anode catalysts with 60 wt.% (Pt) and 10wt.% (PtNi) were tested. The operation of the AEMFC was controlled by means of an in-house-made electronic load with PI-controller (i.e. a feedback controller that has proportional and integral action on control error signal) either at constant current (CC) or at constant voltage (CV). The primary objective was to characterize the Coulombic efficiency (CE) based on the exchange of two electrons and compare the specific energy (Wh kg(-1)) for the direct glucose AEMFC related to the different electrode combinations and electrocatalysts. As a result of these screening tests, two most efficient anode electrodes with Pt and PtNi were selected to be used for further AEMFC studies.
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| 13. |
- Jukka-Pekka, Spets, et al.
(author)
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Towards an Efficient Direct Glucose Anion Exchange Membrane Fuel Cell System with Several Electro-Oxidation Units
- 2017
-
In: International Journal of Electrochemical Science. - : ESG. - 1452-3981. ; 12:5, s. 3697-3708
-
Journal article (peer-reviewed)abstract
- This work covers the direct glucose anion exchange membrane fuel cell (AEMFC) with near-neutralstate electrolyte of 0.1 M [PO4] (tot) having two high-performing anode electrocatalysts (Pt and PtNi) at 37 degrees C and at a glucose concentration of 0.1 M. The cathode catalyst in each test was a Pt supported on carbon (60 wt.%). The PtNi/C had a total metal content of 40 wt.% and the Pt/C 60 wt.%. The operation of the AEMFC was controlled by means of an in-house made electronic load with PI-controller (i.e. a feedback controller, which has proportional and integral action on control error signal). There were two primary objectives with this study. At first, to find out how the electrode modifications of the anode (i.e. by increasing the thicknesses of these electrodes by adding extra carbon) affect the Coulombic efficiency (CE, based on the exchange of two electrons) and the specific energy (SPE, Wh kg(-1)) values of the direct glucose AEMFC. Secondly, investigate how a two-stage fuel cell system with two fuel cells concatenated and used one after the other for the electrochemical oxidation of glucose, influence the CE and SPE values. The results show that the modified PtNi anode shows superior results for the AEMFC compared to our earlier results. As for the two-stage fuel cell system, it increased the average electric power (mWh) and SPE when compared to single fuel cell systems except when the higher selective anode catalyst (Pt) was used in the first fuel cell prior to the fuel cell in the second fuel cell containing the lower selective anode catalyst (PtNi).
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| 14. |
- Kiros, Yohannes, et al.
(author)
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Low energy consumption in chlor-alkali cells using oxygen reduction electrodes
- 2008
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 3:4, s. 444-451
-
Journal article (peer-reviewed)abstract
- An air/oxygen gas diffusion electrode for use as a cathode to replace the traditional hydrogen-evolving electrode in chlor-alkali electrolysis was assessed. Attempts to stabilize the cathode have been addressed in order to circumscribe problems associated with "flooding" or "wetting-in" properties. Variation of the hydrophobic concentration in the gas diffusion layer had a significant effect on the electrochemical tests of both the half-cell and electrolysis of the chlor-alkali cells. Life-tests as well as performance characteristics for both types of cells have shown encouraging results at NaOH concentration levels of ca 8M NaOH and temperatures of 70 and ca. 80 degrees C, respectively. Though cell voltages of about 2V were achieved and thereby reducing the energy consumption by 30-35% compared to the state-of-the-art membrane cell, the contributions of overvoltages were still high compared to the equilibrium potential of about 1.23V. Efforts to limit the individual parts of overvoltages as well as maintenance of the zero-gap cell at least on the anode side have been carried out. Two different kinds of cation exchange membranes have been used for the electrolysis cell. However, the cation exchange membrane with hydrophilic properties having high initial performances showed tendencies of blister formations.
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| 15. |
- Kiros, Yohannes
(author)
-
Metal porphyrins for oxygen reduction in PEMFC
- 2007
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 2:4, s. 285-300
-
Journal article (peer-reviewed)abstract
- A short literature review on alternative catalysts for the cathodic oxygen reduction in acid (H2SO4) and polymer electrolyte membrane fuel cell ( PEMFC) with special emphasis on pyrolyzed macrocycles and precursor materials from metals, organic molecules and N-containing elements has been conducted. Furthermore, various catalytic materials comprising two different concentrations of iron and cobalt tetramethoxyphenyl porphyrins and perovskites were prepared by both the impregnation and precipitation reactions. Screening tests of the individual catalytic materials and their mixtures were carried out in half-cell measurements using the rotating disc electrode (RDE) in 0.5M H2SO4 and at room temperature. Cyclic voltammograms were recorded at a scan rate of 10 mV s(-1) both with and without rotations. The peak potential at 0 rpm was used to study and compare the catalytic activities towards oxygen reduction reaction (ORR). Concentrations of 30wt% Fe and Co/TMPP have shown increased performance characteristics, while those with lower or increased contents, acid-treated and mixed with perovskite have displayed lower activities. Polarization data for the catalyst containing 30wt% FeTMPP was also obtained. Acid leaching of the pyrolysis products has resulted in substantial decrease of the metals from the pyrolysis products supported on carbon. TEM, BET-surface area and EDX analyses on the samples have shown high aggregation of the metals with crystalline structure, surface areas depending on the compositions of the catalysts and increased surface concentration of the metals with absence of nitrogen on the moiety.
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| 16. |
- Li, Shian, et al.
(author)
-
Numerical investigation on the impact of membrane thickness on transport phenomena in PEM fuel cells
- 2020
-
In: International Journal of Electrochemical Science. - : Elsevier BV. - 1452-3981. ; 15, s. 4138-4147
-
Journal article (peer-reviewed)abstract
- A two-dimensional mathematical model is used to investigate the performance and transport characteristics of PEM fuel cells with different membrane thicknesses. The overall cell performance of three cases are presented and compared. In addition, the local temperature, liquid water saturation, water content and current density distributions are analyzed and compared. Results show that performance increases with decreasing membrane thickness and the local transport characteristics is also significantly affected. The ohmic loss is mainly caused by the proton transport process inside fuel cell. And a thinner membrane can enhance water back diffusion process in the membrane which is beneficial to the water management at the anode side.
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| 17. |
- Li, Shian, et al.
(author)
-
Performance and transport characteristics of solid oxide fuel cells with counter flow arrangement
- 2020
-
In: International Journal of Electrochemical Science. - : Elsevier BV. - 1452-3981. ; 15:2, s. 1338-1346
-
Journal article (peer-reviewed)abstract
- In this study, a two-dimensional model including the governing equations of mass, momentum, species, energy and charge, is developed and then applied to investigate the performance and multiphysics transport processes of solid oxide fuel cells with counter-flow arrangement. The current density and power density are calculated and presented, and the distributions of species and temperature are also analyzed. In addition, temperature distributions of fuel cells with varying operating temperature, anode inlet flow velocity and cathode inlet flow velocity are demonstrated. The results show that the temperature gradient increases with increasing operating temperature. And the local temperature decreases with increasing inlet flow velocities, especially the increasing cathode inlet flow velocity.
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| 18. |
- Lowe, Troy A., et al.
(author)
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Chemical Speciation Measurements of Silver Ions in Alkaline Carbonate Electrolytes Using Differential Pulse Stripping Voltammetry on Glassy Carbon Compared With Ion Selective Electrode Measurements
- 2013
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 8:3, s. 3851-3865
-
Journal article (peer-reviewed)abstract
- Given the increasing incorporation of silver nanoparticles as an antibacterial additive in washing machines and textiles, sensitive methods for accurate determination of Ag+ ions in laundry relevant electrolytes (alkaline carbonate) are required. The most widely reported method, the silver ion selective electrode (ISE), lacked sensitivity and accuracy and was affected by the concentration of Na2CO3 in solution. Differential pulse stripping voltammetry (DPSV) on glassy carbon electrodes (GCE) was therefore investigated as an alternative technique. Surface preparation of the GCE surface was essential and a suitable procedure was developed. A linear response was observed from 0 to 180 mg L-1 with a lower detection limit of 500 ng L-1 (5 nM). DPSV was shown to be significantly more sensitive and accurate in determining the Ag+ activity than the silver ISE technique, particularly below 200 nM.
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| 19. |
- Spets, J. -P, et al.
(author)
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Direct glucose fuel cell with the anion exchange membrane in the near-neutral-state electrolyte
- 2012
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 7:12, s. 11696-11705
-
Journal article (peer-reviewed)abstract
- This paper deals with the direct glucose fuel cell with an electrolyte at near-neutral-state pH value at room temperature by incorporating an anion exchange membrane (AEM) that was directly attached to a cathode. The wetted surface of the cathode was exposed to the AEM without implementing hot-pressing. The current-voltage curves were measured and the specific energy values for glucose were calculated for every test. Different concentrations of glucose were used and the results show that the lower the concentration of glucose, the higher is the specific energy, apparently showing higher utilization of the fuel with high Coulombic efficiency.
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| 20. |
- Spets, J. -P, et al.
(author)
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Effect of temperature on a direct glucose anion exchange membrane fuel cell in a near-neutral-state electrolyte
- 2013
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 8:1, s. 1226-1236
-
Journal article (peer-reviewed)abstract
- A direct glucose anion exchange membrane fuel cell (AEMFC) with a near-neutral-state electrolyte was studied at varying temperatures of 20, 30 and 37 ° C at two different concentrations of glucose of 0.1 and 0.3 M and with three concentrations of electrolyte of 0.1, 0.2 and 0.3 M [PO4]tot. The prime objective was to show how specific energy (W kg-1 glucose) of the direct glucose AEMFC is related to the operation temperature and concentrations of the species. Current and voltage values were measured together with the pHs and conductivities of the electrolytes. No component analysis of the final products after the fuel cell operation were done as the oxidation products of glucose is believed to be mainly gluconic acid and unreacted glucose as shown in the low Coulombic efficiency based on the exchange of 24 e-. Temperature, electrolyte and glucose concentrations have shown to have pronounced effect for the achievement of the highest energy capacity of 5.15 Wh kg-1 glucose.
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| 21. |
- Spets, J. -P, et al.
(author)
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The Simultaneous Uses of the Direct-Mode Bioorganic Fuel Cell and the Function Generator for the Enhancement of the Glucose Electro-chemical Oxidation
- 2010
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 5:4, s. 547-555
-
Journal article (peer-reviewed)abstract
- In this study a test of the direct-mode bioorganic fuel cell (DMBFC) in which the fuel and the alkaline electrolyte are mixed with each other at two temperatures of 20 and 35 degrees C are carried out. The direct-mode bioorganic fuel cell is exposed to an externally generated electromagnetic field with simultaneous discharging in order to split the fuel molecule before the electrochemical oxidation at the two operation temperatures. The current-voltage characteristics are measured and analyzed. The liquid phase of the fuel-electrolyte concentration of the glucose was analysed both before and after the electrochemical tests at the operation temperature 20 degrees C. The aim is to continue with the development of the direct-mode glucose fuel cell by increasing the power density range by several mWcm(-2). This type of the fuel cell with glucose as a fuel has increased to the specific capacity levels of 120.8 and 132.7 Ah / kg glucose at the temperatures of 20 degrees C and 35 degrees C, respectively.
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| 22. |
- Sukhrobov, Parviz, et al.
(author)
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A New Non-Enzymatic Amperometric Sensor Based on Nickel Decorated ZIF-8 Derived Carbon Nanoframe for the Glucose Determination in Blood Samples
- 2018
-
In: International Journal of Electrochemical Science. - : ESG. - 1452-3981. ; 13:7, s. 6550-6564
-
Journal article (peer-reviewed)abstract
- The present study demonstrated a highly sensitive non-enzymatic glucose biosensor in real blood samples based on simple evaluated nickel deposited on N-doped porous carbon modified glassy carbon electrode (Ni/NPC/GCE) by applying electrochemical deposition method. The prepared material initially were characterized by cyclic voltammetry, the morphology structure of the as-prepared samples was observed by SEM, and composition, crystals structure of Ni/NPC were identified by SEM mapping and EDS tests. The Ni/NPC/GCE compared with NPC/GCE and NiNPs/GCE performed the best electrocatalytic behavior towards oxidation of glucose in 0.1 M KOH medium. By applied potential of +0.6 V Ni/NPC/GCE showed very high sensitivity of 3753.78 mu AmM(-1)cm(-2) in linear range of 1-7940 mu M with the correlation coefficient of R-2=0.995. The linear ranges get views above the concentration up to 7940 mu M with the detection limit of 0.3 mu M (S/N= 3). Amperometric time responses of prepared electrode towards different glucose concentrations are 0.8-1.3s. Finally, several positive characteristics such as very high sensitivity, weak working potential, nice anti-interference properties, long stability, good selectivity, and comparison with some other non-enzymatic sensors Ni/NPC/GCE executed high sensitivity, low detection limit and wide linear range to glucose sensing, thus the selected electrode is supplying for future glucose level determination design.
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| 23. |
- Sun, Xueli, et al.
(author)
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Electrochemical performances of BSCF cathode materials for ceria-composite electrolyte low temperature solid oxide fuel cells
- 2007
-
In: International Journal of Electrochemical Science. - 1452-3981. ; 2:6, s. 462-468
-
Journal article (peer-reviewed)abstract
- The Ba0.5Sr0.5Co0.2Fe0.8O3 (BSCF) cathode material was synthesized and evaluated for cathode in low temperature solid oxide fuel cells (LTSOFCs). Using Ni as anode, Sm0.2Ce0.8O2(SDC)-carbonate composites as electrolyte and the BSCF as cathode to construct the fuel cell (LTSOFC), maximum power output of 860 mW/cm(2) has been achieved at 500 degrees C. The LTSOFC at a large area, 14 cm(2), has delivered 5 W corresponding to a power density of 358 mW/cm(2) at 510 degrees C. These results have been the first recorded for the best performance of SOFCs at low temperatures.
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| 24. |
- Tan, Jianhong, et al.
(author)
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Electrochemical and Computational Studies on the Corrosion Inhibition of Mild Steel by 1-Hexadecyl-3-methylimidazolium Bromide in HCl Medium
- 2020
-
In: International Journal of Electrochemical Science. - : ESG. - 1452-3981. ; 15:3, s. 1893-1903
-
Journal article (peer-reviewed)abstract
- An imidazolium-based ionic liquid, i.e., 1-Hexadecyl-3-methylimidazolium Bromide (HMIBr), was investigated as a corrosion inhibitor candidate for mild steel in 1 M HCl medium using combined electrochemical and molecular simulation methods. Potentiodynamic polarization results show that HMIBr is a mixed-type inhibitor and suppresses the corrosion process effectively at optimum concentration 10(-3) M with 96.9% inhibition efficiency. Electrochemical impedance spectroscopy (EIS) analysis indicated an increase in the charge transfer resistance with enhance of inhibitor concentration, and confirmed the adsorption of HMIBr on the iron surface. Moreover, density functional theory (DFT) calculations, Monte Carlo as well as molecular dynamics simulations were employed to obtain further insights into the antiseptic mechanism. Our findings have important guiding significance for understanding the corrosion inhibition mechanism and designing new ionic liquid-based inhibitor molecules.
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| 25. |
- Teesetsopon, Pichanan, et al.
(author)
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Photoelectrode Optimization of Zinc Oxide Nanoparticle Based Dye-Sensitized Solar Cell by Thermal Treatment
- 2012
-
In: International Journal of Electrochemical Science. - : Electrochemical Science Group, Serbia. - 1452-3981. ; 7:6, s. 4988-4999
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Journal article (peer-reviewed)abstract
- Interfacial properties at the photoelectrode of dye-sensitized solar cell (DSSC) play a vital role in determining its efficiency. This research examined the role of annealing temperature on the photoelectrode interfaces properties, and to find the annealing temperature that provides the highest overall solar cell efficiency. The electrical characteristics of the DSSC using ZnO nanoparticles photoelectrode annealed at different temperatures were studied using electrochemical impedance spectroscopy (EIS), and the corresponding I-V characteristics were determined. The highest efficiency of the solar cells was obtained when the photoelectrode was annealed at 400°C. This is mainly due to the enhancement in charge collection by better ZnO crystallinity and reduction of interfacial charge transfer resistance at the ZnO/dye/electrolyte interface. Moreover, the electron recombination between transparent conducting oxide substrate and electrolyte was also revealed for the first time by EIS.
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| 26. |
- Zhu, Bin, et al.
(author)
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Studies on Dual Phase Ceria-based Composites in Electrochemistry
- 2006
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In: International Journal of Electrochemical Science. - 1452-3981. ; 1:8, s. 383-402
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Research review (peer-reviewed)abstract
- The ceria-based dual-phase composites have been recently developed as functional electrolytes successful for intermediate and low temperature solid oxide fuel cell applications. These composite materials showed many unique advantages over the conventional single-phase electrolytes, such as superionic conduction in two-phase interfaces, dual proton and oxygen ion conduction resulting in extremely high ion conductivity and high current outputs in fuel cell and other applications, e. g. electrolysis. Interfacial superionic conduction is a characteristic for high conducting dual-phase composites. The composite approach can combine or integrate multi-ion functions, typically, dual H(+) and O(2-)conduction together to enhance the material conductivity and device performance. Dual or hybrid H+ and O(2-)conduction is based on a consideration that both proton (H+) and oxygen ion (O(2-)) are the fuel cell source ions. Proton conduction is important for LTSOFCs since it can be activated easier than oxygen ions in the low temperature (LT, 300-600 degrees C) region. The superionic conduction, dual phase proton and oxygen ion transport make significant conduction and electrical contributions for electrochemical devices. This paper makes a review on these recent studies.
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