2011
DOI: 10.1021/la201526u
|View full text |Cite
|
Sign up to set email alerts
|

Correlation between the Structure and Wettability of Photoswitchable Hydrophilic Azobenzene Monolayers on Silicon

Abstract: Photoresponsive monolayers of hydrophilically substituted azobenzenes have been prepared by reaction on aminosilane monolayers on silicon surfaces. Grafting densities in the 0.2-1.0 molecule/nm(2) range were determined by X-ray reflectometry. The monolayers exhibit reversible photoisomerization, switching from a more hydrophilic trans state to a less hydrophilic cis state upon UV irradiation, in contrast with the usual behavior of most azobenzene monolayers that switch from a less to a more hydrophilic state. … Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...
3
2

Citation Types

4
56
0

Year Published

2012
2012
2024
2024

Publication Types

Select...
8

Relationship

0
8

Authors

Journals

citations
Cited by 57 publications
(60 citation statements)
references
References 44 publications
4
56
0
Order By: Relevance
“…It's easily observed that the UV light induces the progressive decrease of absorbance band around 330 nm accompanied with the slight increase of the absorbance band around 450 nm, which is respectively attributed to the π–π* electronic transition of trans configuration and the n–π* ransition of the cis configuration, indicating the trans – cis isomerization of azo chromophores. For FAzoMA , as seen in Figure (A), photostationary state reached after UV irradiation for about 300 s. The existence of isosbestic points at about 290 and 393 nm is characteristic of the existence of two distinct absorbing species in equilibrium with each other, confirming the trans ‐ cis isomerization . The appearance of isosbestic points indicates that this monomolecular transformation is characterized by the presence of two spectrophotometrically distinguishable species .…”
Section: Resultsmentioning
confidence: 86%
See 2 more Smart Citations
“…It's easily observed that the UV light induces the progressive decrease of absorbance band around 330 nm accompanied with the slight increase of the absorbance band around 450 nm, which is respectively attributed to the π–π* electronic transition of trans configuration and the n–π* ransition of the cis configuration, indicating the trans – cis isomerization of azo chromophores. For FAzoMA , as seen in Figure (A), photostationary state reached after UV irradiation for about 300 s. The existence of isosbestic points at about 290 and 393 nm is characteristic of the existence of two distinct absorbing species in equilibrium with each other, confirming the trans ‐ cis isomerization . The appearance of isosbestic points indicates that this monomolecular transformation is characterized by the presence of two spectrophotometrically distinguishable species .…”
Section: Resultsmentioning
confidence: 86%
“…Distinctly, the polymers show the similar isomerization process under the irradiation of UV light, no matter whether the POSS was incorporated or not. For the polymers, photostationary states reached after UV irradiating for about 420 s. It were reported previously that other polymers containing azobenzene groups in solution finished trans to cis isomerization under UV irradiation for about 30 minutes . In this study, the synthesized polymers in THF solution finished trans to cis photoisomerization within only several minutes.…”
Section: Resultsmentioning
confidence: 99%
See 1 more Smart Citation
“…Liquid crystalline (LC) azobenzene-containing polymers belong to such materials capable of providing a fast response to the light action through a reversible photoinduced E-Z isomerization of azobenzene (Azo) chromophore accompanied by large changes occuring of its molecular size, shape, and polarity [1][2][3] . These structural changes may essentially influence on wettability, 4,5 phase transitions, [6][7][8][9] thin films contracting, [10][11][12][13][14][15][16][17] and surface modification [18][19][20] of polymers. Under irradiation by linearly polarized light the Azo chromophores are known to orient preferentially in the direction perpendicular to the polarization plane of the excitation light (Weigert effect 21 ).…”
Section: Introductionmentioning
confidence: 99%
“…Azobenzene molecule is widely used in polymerization [3] especially in photochemical applications [4], optoelectronic devices [5], optical data storage devices [6] and liquid crystalline polymers [7]. In 2000 Laschitsch and co-workers reported that polymer films containing azobenzene undergo softening upon irradiation with UV light due to the cis-trans isomerisation of azobenzene [8].…”
Section: Introductionmentioning
confidence: 99%