Voltammetry measurements in lithium chloride-lithium oxide (LiCl–Li2O) salt: an evaluation of working electrode materials

Gas exhaust emissions in vehicles are increasingly restrictive in EU and USA. Diesel engines are particularly affected by limitation in hydrocarbons and NOx concentrations. This work presents a screening of working electrode materials to develop a potentiometric sensor, with the most promising material to detect being C2H4 at 550 °C. The device consists of a dense 8YSZ (8 mol% Y2O3 stabilized ZrO2) disk as oxide-ion conducting electrolyte, whereas platinum is screen-printed in the back face as reference electrode. As working electrode, several materials such as Fe0.7Cr1.3O3, ZnCr2O4, Fe2NiO4, La0.8Sr0.2CrO3−δ (LSC), La0.8Sr0.2MnO3 (LSM), and NiO+5%wt Au were tested to detect C2H4. Sensor voltage was measured for several concentrations of C2H4 and CO as these are two of the major oxidizable compounds in a diesel exhaust gas. Fe0.7Cr1.3O3 was selected as the most promising material because of its response to C2H4 and CO. Not only is the response to the individual analytes important, but the C2H4 cross-sensitivity toward CO is also important. Fe0.7Cr1.3O3 showed a good performance to C2H4, with low cross-sensitivity to CO. In addition, when 0.16 ppm of phenanthrene is added, the sensor still has a slightly better response to C2H4 than to CO. Nevertheless, the sensor exposure to high concentrations (>85 ppm) of polycyclic aromatic hydrocarbons led to signal saturation. On the other hand, the operation in wet conditions induces lower sensor sensitivity to C2H4 and higher cross-sensitivity toward CO increase, i.e., the sensor response becomes similar for C2H4 and CO.

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Non-Nernstian potentiometric zirconia sensors: screening of potential working electrode materials

Sensors and Actuators B Chemical ◽

10.1016/0925-4005(93)85041-8 ◽

1993 ◽

Vol 15 (1-3) ◽

pp. 147-150 ◽

Cited By ~ 48

Author(s):

A. Vogel ◽

G. Baier ◽

V. Schüle

Keyword(s):

Electrode Materials ◽

Working Electrode

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Applications of ZnO Nanowires as Electrode Materials in Photosynthetic Bio-Photoelectrochemical Cells

MRS Proceedings ◽

10.1557/opl.2015.606 ◽

2015 ◽

Vol 1772 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Houman Yaghoubi ◽

Anand Kumar Santhanakrishn ◽

Md Khan ◽

J. Thomas Beatty ◽

Arash Takshi

Keyword(s):

Electrode Materials ◽

Protein Complexes ◽

Photocurrent Density ◽

Open Circuit ◽

Zno Nanowires ◽

Current Response ◽

Counter Electrodes ◽

Working Electrode ◽

New Generation ◽

Linker Molecules

ABSTRACTHarvesting solar energy, is only one of the incentives of incorporating photosynthetic proteins in electrochemical devices. Understanding the interface of photosynthetic protein complexes and organic\inorganic underlying electrodes can give rise to development of new generation of nano-bioelectronics for other applications such as sensing, as well. Previous approaches in fabricating photosynthetic bio-hybrid electrochemical solar cells were mainly based on metallic electrodes with protein complexes attached, either directly or through linker molecules. Due to the energy band structure in semiconductors, they potentially can be useful for selective charge transfer in an electrochemical device. In the current study, a two terminal sealed bio-hybrid solar cell device was fabricated comprising of hydrothermally grown ZnO nanowires on fluorine doped tin oxide (FTO) glass working electrode, a Pt counter electrode, and methyl viologen (MV) as a single diffusible redox mediator. The ZnO working electrode was initially characterized using scanning electron microscopy (XRD) and X-ray diffraction (XRD). A solution of dimeric Rhodobacter sphaeroides – light harvesting 1 (RC-LH1) core complexes and redox electrolyte was injected into the cavity between working and counter electrodes. Such structure resulted in ∼0.64 µA.cm-2 photocurrent density and ∼0.24 V open circuit potential difference in the dark and under illumination. Additionally, the device stability tests demonstrated that the current response of such devices remained unchanged after 33 hours storage in the dark.

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Redox Potentials of Samarium and Europium in Molten Lithium Chloride

Zeitschrift für Naturforschung A ◽

10.1515/zna-2001-1110 ◽

2001 ◽

Vol 56 (11) ◽

pp. 754-756 ◽

Cited By ~ 3

Author(s):

Alena Novoselova ◽

Vladimir Shishkin ◽

Vladimir Khokhlov

Keyword(s):

Rare Earth ◽

Lithium Chloride ◽

Glassy Carbon ◽

Total Concentration ◽

Potentiometric Method ◽

Redox Potentials ◽

Temperature Range ◽

Working Electrode ◽

Molten Lithium

Abstract The samarium (III)/(II) and europium (III)/(II) redox potentials in molten lithium chloride were measured using the direct potentiometric method in the temperature range from 923 to 1094 K. Glassy carbon was used as the indifferent working electrode, and the standard chlorine electrode as a reference. The total concentration of rare-earth chlorides dissolved in molten lithium chloride did not exceed 4.5 mol%.

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Preparation of electrochemically active silicon nanotubes in highly ordered arrays

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.4.73 ◽

2013 ◽

Vol 4 ◽

pp. 655-664 ◽

Cited By ~ 9

Author(s):

Tobias Grünzel ◽

Young Joo Lee ◽

Karsten Kuepper ◽

Julien Bachmann

Keyword(s):

Photoelectron Spectroscopy ◽

Electrode Materials ◽

Negative Electrode ◽

Lithium Ion ◽

Atomic Layer ◽

Preparative Method ◽

Thermal Reduction ◽

Lithium Oxide ◽

Silicon Nanotubes ◽

Ordered Arrays

Silicon as the negative electrode material of lithium ion batteries has a very large capacity, the exploitation of which is impeded by the volume changes taking place upon electrochemical cycling. A Si electrode displaying a controlled porosity could circumvent the difficulty. In this perspective, we present a preparative method that yields ordered arrays of electrochemically competent silicon nanotubes. The method is based on the atomic layer deposition of silicon dioxide onto the pore walls of an anodic alumina template, followed by a thermal reduction with lithium vapor. This thermal reduction is quantitative, homogeneous over macroscopic samples, and it yields amorphous silicon and lithium oxide, at the exclusion of any lithium silicides. The reaction is characterized by spectroscopic ellipsometry for thin silica films, and by nuclear magnetic resonance and X-ray photoelectron spectroscopy for nanoporous samples. After removal of the lithium oxide byproduct, the silicon nanotubes can be contacted electrically. In a lithium ion electrolyte, they then display the electrochemical waves also observed for other bulk or nanostructured silicon systems. The method established here paves the way for systematic investigations of how the electrochemical properties (capacity, charge/discharge rates, cyclability) of nanoporous silicon negative lithium ion battery electrode materials depend on the geometry.

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Polyaniline nanostructures expedient as working electrode materials in supercapacitors

Applied Physics A ◽

10.1007/s00339-013-7920-z ◽

2013 ◽

Vol 115 (1) ◽

pp. 189-197 ◽

Cited By ~ 14

Author(s):

Venkata Ramana Gedela ◽

Vadali Venkata Satya Siva Srikanth

Keyword(s):

Electrode Materials ◽

Working Electrode

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A novel ligand with –NH2 and –COOH-decorated Co/Fe-based oxide for an efficient overall water splitting: dual modulation roles of active sites and local electronic structure

Catalysis Science & Technology ◽

10.1039/d0cy01109f ◽

2020 ◽

Vol 10 (18) ◽

pp. 6266-6273

Author(s):

Yalan Zhang ◽

Zebin Yu ◽

Ronghua Jiang ◽

Jung Huang ◽

Yanping Hou ◽

...

Keyword(s):

Electronic Structure ◽

Water Splitting ◽

Energy Demand ◽

Active Sites ◽

Electrode Materials ◽

Global Energy ◽

Overall Water Splitting ◽

Local Electronic Structure ◽

Electrochemical Water Splitting

Excellent electrochemical water splitting with remarkable durability can provide a solution to satisfy the increasing global energy demand in which the electrode materials play an important role.

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