Surface Induced Hydrogen-Bonded Macrocluster Formation of Methanol on Silica Surfaces

Langmuir ◽  
2005 ◽  
Vol 21 (21) ◽  
pp. 9402-9405 ◽  
Author(s):  
Masashi Mizukami ◽  
Yasuhiro Nakagawa ◽  
Kazue Kurihara
2018 ◽  
Vol 47 (12) ◽  
pp. 4301-4306 ◽  
Author(s):  
Niladri Maity ◽  
Samir Barman ◽  
Edy Abou-Hamad ◽  
Valerio D'Elia ◽  
Jean-Marie Basset

Unveiling a clean, selective chlorination method for the quantitative substitution of well-defined non-hydrogen bonded silanol groups of the silica surface.


2003 ◽  
Vol 56 (10) ◽  
pp. 1071 ◽  
Author(s):  
Masashi Mizukami ◽  
Kazue Kurihara

We have investigated the adsorption of 1- and 2-propanol on silica surfaces from their mixtures with cyclohexane using a combination of colloidal probe atomic force microscopy, adsorption excess isotherms, and FTIR spectroscopy in the ATR mode. The adsorption isotherm indicated that a similar amount of each alcohol was adsorbed on the silica surfaces. FTIR spectra revealed that 1-propanol adsorbed on the surface employing hydrogen-bonding between the surface silanol groups and the hydroxyl groups of 1-propanol as well as between the hydroxyl groups of 1-propanol in the form of a linear zig-zag structure. This structure is similar to the linear hydrogen-bonded structure of ethanol, which we have found on silica and called a ‘surface molecular macrocluster’ (M. Mizukami, M. Moteki, K. Kurihara, J. Am. Chem. Soc. 2002, 124, 12 889). The contact of adsorbed layers of 1-propanol on the opposed silica surfaces brought about the long-range attraction extending to 69 ± 9 nm at 0.1 mol-% 1-propanol. 2-Propanol was also adsorbed on the surface by the hydrogen-bonding, however, in the form of a cyclic structure. No long-range attraction was observed in the 2-propanol/cyclohexane binary liquids at 0.1–6.0 mol-%. The absence of a long-range attraction can be explained by the cyclic aggregation structure of 2-propanol on the surface.


2005 ◽  
Vol 34 (2) ◽  
pp. 228-229
Author(s):  
Guolun Zhong ◽  
Masashi Mizukami ◽  
Isao Fukuchi ◽  
Takashi Miyahara ◽  
Kazue Kurihara

2002 ◽  
Vol 124 (43) ◽  
pp. 12889-12897 ◽  
Author(s):  
Masashi Mizukami ◽  
Masashi Moteki ◽  
Kazue Kurihara

1969 ◽  
Vol 47 (12) ◽  
pp. 2237-2247 ◽  
Author(s):  
R. P. Young

Infrared spectra in the region 4000–1300 cm−1 have been obtained of acetic acid, acetyl chloride, acetic anhydride, propionic acid, and propionyl chloride adsorbed on discs of pressed silica powder. In all cases the spectra showed the presence of both the simple hydrogen-bonded species[Formula: see text]where X = OH, Cl, or O.CO.R and Si* represents a surface silicon atom, and also chemisorbed surface ester groups R.CO.O—Si*. The latter were characterized by a νC=O frequency in the 1760–1740 cm−1 region, whereas in the case of hydrogen-bonded physical adsorption, the νC=O frequency was about 20–30 cm−1 lower than that of the same molecule in the vapor phase. At high temperatures (150–200 °C) the water or hydrogen chloride eliminated in the surface esterification reaction was desorbed, and high conversions of surface OH to surface ester groups were observed. Under these conditions the carboxylic acid was formed from both the chloride and the anhydride; the latter was also produced at room temperature from the acid chloride. A scheme is suggested for the equilibration of these compounds on hydroxylated silica surfaces. The chemisorbed ester groups were susceptible to hydrolysis by water vapor, thus regenerating the original silanol OH groups.


2019 ◽  
Vol 116 (5) ◽  
pp. 1520-1525 ◽  
Author(s):  
Jenée D. Cyran ◽  
Michael A. Donovan ◽  
Doris Vollmer ◽  
Flavio Siro Brigiano ◽  
Simone Pezzotti ◽  
...  

Interfaces between water and silicates are ubiquitous and relevant for, among others, geochemistry, atmospheric chemistry, and chromatography. The molecular-level details of water organization at silica surfaces are important for a fundamental understanding of this interface. While silica is hydrophilic, weakly hydrogen-bonded OH groups have been identified at the surface of silica, characterized by a high O-H stretch vibrational frequency. Here, through a combination of experimental and theoretical surface-selective vibrational spectroscopy, we demonstrate that these OH groups originate from very weakly hydrogen-bonded water molecules at the nominally hydrophilic silica interface. The properties of these OH groups are very similar to those typically observed at hydrophobic surfaces. Molecular dynamics simulations illustrate that these weakly hydrogen-bonded water OH groups are pointing with their hydrogen atom toward local hydrophobic sites consisting of oxygen bridges of the silica. An increased density of these molecular hydrophobic sites, evident from an increase in weakly hydrogen-bonded water OH groups, correlates with an increased macroscopic contact angle.


2001 ◽  
Vol 123 (7) ◽  
pp. 1545-1546
Author(s):  
James S. Nowick ◽  
De Michael Chung ◽  
Kalyani Maitra ◽  
Santanu Maitra ◽  
Kimberly D. Stigers ◽  
...  

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