Nexafs Studies of Unsaturated Carboxylic Acids and Alcohols Adsorbed on the Si(111)(7×7) Surface

1986 ◽  
Vol 77 ◽  
Author(s):  
D. A. Outka ◽  
J. Stöhr ◽  
R. J. Madix ◽  
H. H. Rotermund ◽  
B. Hermsmeier ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Carboxylic Acid ◽  
Acrylic Acid ◽  
Formic Acid ◽  
Silicon Substrate ◽  
Silicon Surface ◽  
Alcohol Group ◽  
Triple Bonds ◽  
Unsaturated Carboxylic Acids ◽  
Propiolic Acid

ABSTRACTThe adsorption of formic acid (HCOOH), acrylic acid (CH2= CHCO2H), propiolic acid (HC=CCO2H), and the corresponding alcohols on the Si(111)(7×7) surface have been investigated by NEXAFS. In each case, well-defined dipole transitions to σ* and π* molecular orbital s were observed above the C and 0 K-edges and used to probe the orientation and chemistry of these molecules on this silicon surface. Monolayer coverages of these molecules on silicon, bond strongly to the silicon surface via the carboxylic acid or alcohol group. In contrast, the C-C double and triple bonds of these molecules do not react initially with the silicon surface. Upon heating, however, the C-C double and triple bonds which are held in proximity to the surface by the carboxylic acid or alcohol group, are lost either by polymerization on the surface or reaction with the silicon substrate. These results illustrate the capabilities of NEXAFS to investigate molecular orientations on surfaces and the electronic structure of polyatomic adsorbates.

scholarly journals CC-stretched formic acid: isomerisation, dimerisation, and carboxylic acid complexation

2021 ◽  
Author(s):  
Katharina A. E. Meyer ◽  
Arman Nejad
Keyword(s):  
Carboxylic Acid ◽  
Formic Acid ◽  
Vibrational Band ◽  
Propiolic Acid

The cis–trans-isomerism of the propiolic acid monomer (HCC–COOH) is examined with linear Raman jet spectroscopy, yielding the first environment-free vibrational band centres of a higher-energy cis-rotamer beyond formic acid (HCOOH) in addition to all fundamentals and a large number of hot and combination/overtone bands of the trans-conformer.

Conformational equilibria in carboxylic acid bimolecules: a rotational study of acrylic acid–formic acid

2013 ◽  
Vol 15 (8) ◽  
pp. 2917 ◽  
Author(s):  
Gang Feng ◽  
Qian Gou ◽  
Luca Evangelisti ◽  
Zhining Xia ◽  
Walther Caminati
Keyword(s):  
Carboxylic Acid ◽  
Acrylic Acid ◽  
Formic Acid ◽  
Conformational Equilibria

scholarly journals Regioselective Base-induced Condensations of Acrylic Acid Derivatives

1999 ◽  
Vol 23 (3) ◽  
pp. 174-175
Author(s):  
E. Abdel-Ghani
Keyword(s):  
Carboxylic Acid ◽  
Acrylic Acid ◽  
Dicarboxylic Acid ◽  
Ethyl Acetoacetate ◽  
Tobacco Necrosis Virus ◽  
Necrosis Virus ◽  
Antiviral Activities

The orientation of cyclization of the reaction of methyl aroylacrylate (1) and aroylacrylic acid (8) with ethyl acetoacetate and/or thiourea leading to the formation of 4-aroylmethylcyclopentane-1,3-dione (2) 5-aryl-3-oxocyclohexene-1,2-dicarboxylic acid (9), 2-imino-5-aroylmethylthiazolidin-4-one (11) and 6-aryl-2-sulfonylpyrimidine-4-carboxylic acid (14) depends on the medium employed; some compounds show moderate antiviral activities against tobacco necrosis virus.

Surface Reactions and Electronic Structure of Carboxylic Acid Porphyrins Adsorbed on TiO2(110)

2021 ◽  
Author(s):  
Daniel Wechsler ◽  
Priscila Vensaus ◽  
Nataliya Tsud ◽  
Hans-Peter Steinrück ◽  
Ole Lytken ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Carboxylic Acid ◽  
Surface Reactions

Electrochemical oxidation of 5-hydroxymethylfurfural on ternary metal-organic frameworks nanoarrays: enhancement from electronic structure modulation

2021 ◽  
Author(s):  
Xiaojue Bai ◽  
Wenxiu He ◽  
Xingyu Lu ◽  
Yu Fu ◽  
Wei Qi
Keyword(s):  
Electronic Structure ◽  
Carboxylic Acid ◽  
Electrochemical Oxidation ◽  
Rational Design ◽  
Metal Organic Frameworks ◽  
Highly Active ◽  
Ternary Metal ◽  
Metal Organic ◽  
Structure Modulation

The rational design and exploitation of highly active and stable catalysts for the electrochemical oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to valuable chemical 2,5-furandi-carboxylic acid (FDCA), is of great significance. Herein,...

Micro- and Nanotextured Silicon for Antireflective Coatings of Solar Cells

2016 ◽  
Vol 39 ◽  
pp. 89-95 ◽  
Author(s):  
Anatoly Druzhinin ◽  
Valery Yerokhov ◽  
Stepan Nichkalo ◽  
Yevhen Berezhanskyi
Keyword(s):  
Solar Cells ◽  
Conversion Efficiency ◽  
Silicon Substrate ◽  
Chemical Etching ◽  
Silicon Surface ◽  
Crystalline Silicon ◽  
Silicon Surfaces ◽  
Antireflective Coatings ◽  
High Conversion Efficiency ◽  
Industrial Use

The paper deals with obtaining of textured silicon surfaces by chemical etching. As a result of experiments based on the modification and optimization of obtaining a textured silicon, several methods of chemical texturing of the crystalline silicon surface were developed. It was shown that modified isotropic and anisotropic etching methods are applicable to create a microrelief on the surface of silicon substrate. These methods in addition to their high conversion efficiency can be used for both mono- and multicrystalline silicon which would ensure their industrial use.

α-CYANO-β-ARYLACRYLIC ACIDS

1945 ◽  
Vol 23b (2) ◽  
pp. 84-87 ◽  
Author(s):  
C. Y. Hopkins ◽  
Mary Chisholm ◽  
Ruth Michael
Keyword(s):  
Carboxylic Acid ◽  
Acrylic Acid

α-Cyano-β-arylacrylic acids have been prepared by condensing the following aldehydes with sodium cyanoacetate: 1-naphthaldehyde, 2,3-dimethoxybenzaldehyde, 3,4-diethoxybenzaldehyde, 6-chloropiperonal, 4-isopropylbenzaldehyde, 2-acetoxy-3-methoxybenzaldehyde, 2-hydroxy-3-methoxybenzaldehyde. The last-named gave α-cyano-β (2-hydroxy-3-methoxyphenyl) acrylic acid, which was readily converted to 8-methoxycoumarin-3-carboxylic acid.

Chemical Modification of the Porous Silicon Surface

1994 ◽  
Vol 358 ◽  
Author(s):  
Eric J. Lee ◽  
James S. Ha ◽  
Michael J. Sailor
Keyword(s):  
Porous Silicon ◽  
Chemical Modification ◽  
Formic Acid ◽  
Gas Phase ◽  
Silicon Surface ◽  
Chemical Vapor ◽  
Luminescence Quenching ◽  
Porous Silicon Surface ◽  
Phase Water ◽  
Surface Modified

ABSTRACTThe porous silicon (PS) surface is derivatized with ethanol, triethylsilanol and formic acid as well as oxidized with water. The two reactions used to prepare these surfaces are discussed, and FTIR spectra of the products are presented. Surface-modified PS retains 10-40% of its original photoluminescence. PS-derivatives display reversible luminescence quenching by gas phase water, ethanol, acetonitrile and benzene. The extent of quenching varies with different PS-derivatives depending on the interaction of the chemical vapor with the modified PS surfaces.

Si Whisker Growth by Hydrogen Radical using Hot Filament CVD Reactor

2007 ◽  
Vol 1018 ◽  
Author(s):  
Hiroshi Nagayoshi ◽  
Suzuka Nishimura ◽  
Kazutaka Terashima ◽  
Nobuo Matsumoto ◽  
Alexander G. Ulyashin
Keyword(s):  
Residence Time ◽  
Silicon Substrate ◽  
Silicon Surface ◽  
Whisker Growth ◽  
Silicon Hydride ◽  
Particle Layer ◽  
Hot Filament Cvd ◽  
Silicon Whisker ◽  
Hydrogen Radical ◽  
Hot Filament

AbstractThis paper describes the growth mechanism of silicon whisker on a silicon substrate using hot filament CVD reactor. Only hydrogen is used as source gas. The particle layer could be obtained at high filament current condition under hydrogen ambient. XPS analysis result suggests that the particle is composed of tungsten silicide. The deposition condition of the particle layer is much depended on the substrate size, surface condition and the distance between the substrate and the filament. The experimental results suggest that the silicon hydride, which generated at the silicon surface by hydrogen radical etching, react with the tungsten filament material around the filament, depositing on the silicon substrate. The silicon surface is etched by hydrogen radical and its resultant surface morphology is much depended on the particle deposition pattern. Many silicon whiskers, which diameter is varied from 10 to 50 nm, are observed on the textured silicon surface when the residence time of the source gas in the reactor is long. Each whisker has a silicon particle on their tip. The silicon hydride generated by the hydrogen radical etching is much absorbed to the silicide particle when the source gas residence time is long, enabling the silicon whisker growth from the particle. The results suggest that nm size whisker structure is much stable compare to the bulk silicon against etching reaction.

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