Microscopic modelling of adsorption and the generalised surface layer hypothesis

1981 ◽  
Vol 59 (13) ◽  
pp. 2072-2079 ◽  
Author(s):  
M. V. Sangaranarayanan ◽  
S. K. Rangarajan
Keyword(s):  
Surface Layer ◽  
Organic Compounds ◽  
Molecular Level ◽  
Neutral Molecule ◽  
Potential Difference ◽  
Electrolyte Interface ◽  
State Models ◽  
Microscopic Modelling

Two- and three-state models for the adsorption of organic compounds at the electrode/electrolyte interface are proposed. Different size requirements, if any, for the neutral molecule and the adsorbing solvent are also considered. It is shown how the empirical, generalised surface layer (GSL) relationship (between the potential difference and the electrode charge) formulated by Damaskin et al. can be understood at the molecular level.

Surface Layer Fluorination of TiO2 Electrodes for Electrode Protection LiBs: Fading the Reactivity of the Negative Electrode/Electrolyte Interface

2019 ◽  
Vol 166 (10) ◽  
pp. A1905-A1914 ◽  
Author(s):  
Youn Charles-Blin ◽  
Delphine Flahaut ◽  
Jean-Bernard Ledeuil ◽  
Katia Guérin ◽  
Marc Dubois ◽  
...  
Keyword(s):  
Surface Layer ◽  
Negative Electrode ◽  
Electrolyte Interface

scholarly journals Molecular-level electrochemical doping for fine discrimination of volatile organic compounds in organic chemiresistors

2020 ◽  
Vol 8 (33) ◽  
pp. 16884-16891 ◽  
Author(s):  
Sooncheol Kwon ◽  
Yusin Pak ◽  
Bongseong Kim ◽  
Byoungwook Park ◽  
Jehan Kim ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Solid State ◽  
Organic Compounds ◽  
Room Temperature ◽  
Molecular Level ◽  
Interfacial Area ◽  
Volatile Organic ◽  
Molecular Scale ◽  
Ppm Level ◽  
State Ionic

A blend of π-CPs and a solid-state ionic liquid provides an enlarged interfacial area at the molecular scale, thereby enabling two-terminal organic chemiresistors (TOCs) with fine discriminatory abilities for sub-ppm-level VOCs at room temperature.

scholarly journals SURFACE TENSION OF SERUM

1922 ◽  
Vol 35 (5) ◽  
pp. 707-735 ◽  
Author(s):  
P. Lecomte du Noüy
Keyword(s):  
Surface Tension ◽  
Surface Layer ◽  
Free Surface ◽  
Organic Compounds ◽  
Sodium Oleate ◽  
Mean Value ◽  
Physiological Solution ◽  
Optimum Concentration ◽  
Initial Value ◽  
Ring Method

The application of the ring method to the measurement of solutions of serum and of certain organic compounds has brought forth new facts, mainly the decrease of the surface tension of such solutions in function of time. 1. In serum diluted at such a low concentration as 1:1,000,000 in NaCl, physiological solution, the surface tension of the liquid is lowered by 3 or 4 dynes in 2 hours; at 1:100,000, by about 11 dynes (mean value) in 2 hours, and by 20 dynes in 24 hours; at 1:10,000 by about 13 to 16 dynes in 2 hours. 2. The drop in surface tension is much more rapid in the first 30 minutes and follows generally the law of adsorption in the surface layer in function of the time. 3. Stirring or shaking after the drop causes the surface tension to rise, but generally below its initial value. 4. The same phenomena occur when using sodium oleate, glycocholate, or saponin instead of serum. 5. For every serum, as well as for the substances mentioned above a maximum drop occurs in certain conditions at a given optimum concentration. 6. Not only are the substances which lower the surface tension adsorbed in the surface layer, in the case in which they are present with crystalloids, but also the crystalloids themselves, in contradiction to Gibbs' statement. This is plainly shown by the evaporation of such solutions in watch-glasses which, instead of a small group of sharp, large, well defined crystals at the bottom, leaves a white disc almost as large as the initial free surface itself, due to the liberation of the salt by the surface layer as it crawls down the concave surface of the glass. 7. In these conditions, solutions of serum are characterized by a very peculiar periodic and concentric distribution of the crystals, at a concentration of 1:100 only. The same ring-like aspect is observed with sodium oleate, glycocholate, and saponin, but not at the same concentration, as was to be expected, since serum is a solution in itself.

Revealing the electronic character of the positive electrode/electrolyte interface in lithium-ion batteries

2017 ◽  
Vol 19 (41) ◽  
pp. 28381-28387 ◽  
Author(s):  
Giorgia Zampardi ◽  
Rafael Trocoli ◽  
Wolfgang Schuhmann ◽  
Fabio La Mantia
Keyword(s):  
Surface Layer ◽  
Lithium Ion Batteries ◽  
High Voltage ◽  
Cathode Materials ◽  
Lithium Ion ◽  
Positive Electrode ◽  
Electrolyte Interface ◽  
Electronic Character

It is not blocking! A surface layer formed at the interface of high voltage cathode materials is an apparent SEI.

Oxygen Reduction on Sodium Tungsten Bronze Electrodes and the Effects of Adsorbed Platinum

1979 ◽  
Vol 32 (11) ◽  
pp. 2343 ◽  
Author(s):  
RA Fredlein
Keyword(s):  
Surface Layer ◽  
Oxygen Reduction ◽  
Tungsten Bronze ◽  
Potential Difference ◽  
Equilibrium Potential ◽  
Flat Band ◽  
Potential Range ◽  
Sodium Tungsten ◽  
Tafel Slopes ◽  
Sodium Tungsten Bronze

The Tafel slopes for oxygen reduction on sodium tungsten bronze electrodes are changed from -4RT/F to -2RT/F by adsorption of platinum from solution. Adsorbed platinum reduces the time to attain steady-state conditions but does not catalyse the reaction. Photo-excitation experiments show that the flat band potential is a function of CH+. Results are interpreted in terms of a thin surface layer of low donor density which is non-degenerate in the potential range of oxygen reduction. It is shown that, without adsorbed platinum, changes in the equilibrium potential difference across the surface layer equal those across the Helmholtz layer due to the presence of hydrogen donors in the lattice and results in -4RT/F Tafel slopes. It is proposed that adsorbed platinum forms surface states pinning the Fermi level at the surface and causing changes in the potential difference to occur entirely across the Helmholtz layer; this results in -2RT/F slopes.

1. Introduction

2017 ◽  
pp. 1-5
Author(s):  
Graham Patrick
Keyword(s):  
Organic Chemistry ◽  
Organic Compounds ◽  
Molecular Level ◽  
Modern Society ◽  
Specialist Field ◽  
Structure Properties ◽  
Carbon Based

Organic chemistry is the study of carbon-based compounds in terms of their structure, properties, and synthesis. One reason for considering organic chemistry as a specialist field is because of the vast numbers of different organic compounds that can be synthesized—far more than would be possible for any other element. For over a hundred years, organic chemists have contributed vastly to our understanding of life at the molecular level, and produced novel compounds that have revolutionized modern society. The Introduction explains that there have been many benefits, but also some drawbacks. New discoveries can produce problems that affect health and the environment if they are not used with due care and responsibility.

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