Electrode substrate

Redox flow Positive electrode, negative electrode substrate, electrocatalyst support, current collector, bipolar separator... 

Composite structures that consist of carbon particles and a polymer or plastic material are useful for bipolar separators or electrode substrates in aqueous batteries. These structures must be impermeable to the electrolyte and electrochemical reactants or products. Furthermore, they must have acceptable electronic conductivity and mechanical properties. The physicochemical properties of carbon blacks, which are commonly used, have a major effect on the desirable properties of the conductive composite structures. Physicochemical properties such as the surface... 

The value of Eff is affected by many experimental conditions other than the electrolyte and anode materials. The experimental conditions include such factors as the cell configuration, electrode orientation, electrode surface area, working electrode substrate, charge-discharge currents, charge quantity, and amount of electrolyte. 

Some of the transition metal macrocycles adsorbed on electrode surfaces are of special Interest because of their high catalytic activity for dloxygen reduction. The Interaction of the adsorbed macrocycles with the substrate and their orientation are of Importance In understanding the factors controlling their catalytic activity. In situ spectroscopic techniques which have been used to examine these electrocatalytlc layers Include visible reflectance spectroscopy surface enhanced and resonant Raman and Mossbauer effect spectroscopy. This paper Is focused principally on the cobalt and Iron phthalocyanlnes on silver and carbon electrode substrates. 

Of special Interest as O2 reduction electrocatalysts are the transition metal macrocycles In the form of layers adsorptlvely attached, chemically bonded or simply physically deposited on an electrode substrate Some of these complexes catalyze the 4-electron reduction of O2 to H2O or 0H while others catalyze principally the 2-electron reduction to the peroxide and/or the peroxide elimination reactions. Various situ spectroscopic techniques have been used to examine the state of these transition metal macrocycle layers on carbon, graphite and metal substrates under various electrochemical conditions. These techniques have Included (a) visible reflectance spectroscopy (b) laser Raman spectroscopy, utilizing surface enhanced Raman scattering and resonant Raman and (c) Mossbauer spectroscopy. This paper will focus on principally the cobalt and Iron phthalocyanlnes and porphyrins. 

Inner electrode Substrate electrode Intermediate electrode External electrode... 

A uniform monolayer surface depends upon it having been deposited on a flat electrode substrate. Impressive flatness can be achieved with the semi-metal graphite, a lamellar structure with weak van der Waals forces between the layers. A clean... 

Lee and Reed have modified the MCBJ measurements for 1,4-benzenedithiol (2), and have used the Si electrode substrate as a gate electrode to find that the conductivity through the benzenedithiolate bonded to two Au shards showed evidence of FET behavior [140]. However, these results are controversial (van der Zant HSJ, 2010, private communication). 

When Xe/y —> 0, catalysis vanishes. In the converse situation, where Xe/y oo, an interesting extreme behavior is observed. Substrate consumption is so rapid that substrate diffusion from the bulk of the solution to the electrode substrate becomes rate limiting. The cyclic voltammetric response... 

M. A. Decrecente, G. K. Layden, and R. A. Pike. Fibrillar carbon fuel cell electrode substrates and method of manufacture. US Patent 4,064,207 (1997). 

P. Wilde, M. Maendle, J. Steinbart, and H. Leinfelder. Carbon fiber electrode substrate for electrochemical cells. CA2424948 (2003). 

S. A. Gampbell, J. Stumper, D. P. Wilkinson, and M. T. Davis. Porous electrode substrate for an electrochemical fuel cell. US Patent 5863673 (1999). 

M. C. Johnson, D. P. Wilkinson, C. P. Asman, M. L. Bos, and R. J. Potter. Electrochemical fuel cell with an electrode substrate having an in-plane non-uniform structure for control of reactant and product transport. US Patent 5840438 (1998). 

J. J. Zhang, K. M. Colbow, and D. P. Wilkinson, lonomer impregnation of electrode substrates for improved fuel cell performance. US Patent 6,187,467 (2001). 

Nafion, an insulator perfiuorinated ionomer, has also been successfully used for preparing CNT-based electrodes [108,109]. It results in a good material for confining CNTs on an electrode substrate and also has capabilities of CNT solubilization and ion-exchange properties. 

An ideal electrolyte solute for ambient rechargeable lithium batteries should meet the following minimal requirements (1) It should be able to completely dissolve and dissociate in the nonaqueous media, and the solvated ions (especially lithium cation) should be able to move in the media with high mobility. (2) The anion should be stable against oxidative decomposition at the cathode. (3) The anion should be inert to electrolyte solvents. (4) Both the anion and the cation should remain inert toward the other cell components such as separator, electrode substrate. 

Adsorption of putidaredoxin on gold electrodes has been studied using dynamic spectroscopic ellipsometry and differential capacitance measurements [307]. In Ref. 307, a method for the measurement of metal surface optical perturbation during protein adsorption at a constant potential has been described. The method is based on the concept that the charged transition layer develops between the electrode substrate and the adsorbate. 

A transparent electrode substrate was prepared by coating indium tin oxide (ITO) on a glass substrate and washing the substrate. ITO was then patterned using a photoresist resin and an etchant to specified patterns and the substrate washed. A hole injection layer was formed by coating a selected experimental agent dissolved in toluene to a thickness of about 50 nm and baking at 110°C for 1 hour. 

However, there is a second case in respect to bonding. It is possible that the rds is not a discharge of X onto M, an atom in the electrode substrate, but instead is the desorption of an adsorbed X from the surface. Obviously, then, a strong bond between the electrode substrate, M, and X, instead of causing a greater velocity of the reaction,... 

X-ray diffraction (XRD) is a routine method for determining crystal lattice parameters and molecular structure. The application of XRD to modified electrodes has been limited, particularly for actual molecular structure determination. First, such experiments presuppose a single-crystal electrode substrate. Second, the small amount of sample present in a thin film on an electrode surface means that the scattered intensities will be restrictively low, at least for commonly available x-ray sources [67]. However, if one is fortunate enough to have access to a synchrotron, such experiments are quite feasible. For details, the reader is directed to an excellent review by Toney and Melroy [68]. On the other hand, powder diffraction experiments with Cu or Mo Ka anode sources are straightforward, and can yield lattice-constant data in situ. For example, Ikeshoji and Iwasaki measured lattice constants for Prussian blue films (discussed earlier) on gold electrode surfaces [69]. 

General Technique for Chlorophyll Utilization. In photoelectrochemical measurements, the methods commonly employed for preparing Chi interfacial layers on electrode substrates are solvent evaporation, electrodeposition (for crystalline Chi), and monolayer deposition techniques, as outlined previously. 

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