Molecular State and Distribution of Fullerenes Entrapped in Sol−Gel Samples

Tran, Chieu D.; Grishko, Victor I.; Challa, Santhosh

doi:10.1021/jp801874c

Cited by 9 publications

(16 citation statements)

References 37 publications

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“…6 For example, the development of hybrid materials for 1 O 2 photosensitization is an active research field. [7][8][9][10][11][12][13] The main issues to be addressed are the stability of the PS (minimal bleaching or photodegradation), the achievement of high 1 O 2 quantum yields, the inertness of the support and chemical grafting of the PS to it. DCA meets the first two conditions, but it is difficult to functionalize due to the poor solubility of the precursor molecules in most solvents.…”

Section: Introductionmentioning

confidence: 99%

A new cyanoaromatic photosensitizer vs. 9,10-dicyanoanthracene: systematic comparison of the photophysical properties

Blanc

Pigot

Cugnet

et al. 2010

Phys. Chem. Chem. Phys.

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The cyanoanthracene derivative, benzo[b]triphenylene-9,14-dicarbonitrile (1) can be prepared readily with a graftable function while maintaining (1)O(2) photosensitizing properties comparable to those of the standard compound 9,10-dicyanoanthracene (DCA). In view of the high potential of the derivatives of 1 for photooxidation reactions under heterogeneous conditions, we compared the photophysical properties of 1 in solution with those of DCA. In pursuing the comparison of 1 and DCA, we observed small but significant changes of the vibronic bands in the electronic absorption spectra of DCA in different solvents, which were well correlated with solvent polarity, similar to the pyrene polarity scale. The main difference between 1 and DCA is in the emission properties: we observed a much stronger sensitivity of the fluorescence emission spectrum to the electron-donating ability of the solvent than for DCA. The emission spectrum of 1 is in general structureless with a large Stokes shift. The ability of the singlet state of 1 to participate in charge transfer interactions with electron-donating solvents is proposed to account for these results. It makes 1 a highly sensitive probe to the surrounding medium. Reversible reduction was observed for both photosensitizers, with a small shift to more negative potentials for 1 compared to DCA. The reduction potential of the first singlet excited state is of the same order of magnitude in both cases. Several photo-oxidation reactions sensitized by 1 and DCA are compared in homogeneous solution and at the gas-solid interface by embedding 1 and DCA in silica monoliths. Our results confirmed the dual character of both cyanoanthracene derivatives as electron transfer and energy transfer sensitizers, highly efficient for singlet oxygen production.

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Section: Introductionmentioning

confidence: 99%

A new cyanoaromatic photosensitizer vs. 9,10-dicyanoanthracene: systematic comparison of the photophysical properties

Blanc

Pigot

Cugnet

et al. 2010

Phys. Chem. Chem. Phys.

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“…The high sensitivity (single pixel resolution), fast temporal (milliseconds), and high spatial resolution ($mm) of this imaging microscope, make it possible for us to use this multispectral imaging microscope for studies and measurements that, to date, have not been possible using existing techniques (Fischer and Tran 1999a;Fischer and Tran 1999b;Tran 2000;2001;2003;2005). These include photo induced changes of a single unit micron-size cell in temperature-sensitive liquid crystals as a function of time and wavelength, and the determination of molecular state and distribution of fullerenes entrapped in sol-gel samples (Fischer and Tran 1999a;Fischer and Tran 1999b;Khait, Smirnov, and Tran 2001;Tran 2000;2001;2003;2005;Tran, Grishko, and Challa 2008).…”

Section: Determination Of Chemical Homogeneity Of Fire Retardant Polymentioning

confidence: 99%

“…The acousto-optic tunable filter (AOTF) based NIR multispectral imaging microscope used in this work is similar to those used in previous studies (Khait, Smirnov, andTran 2001, Tran 2003;2005;Tran, Grishko, and Challa 2008;Mejac et al 2009) except for the replacement of the focusing microscopic lenses in the microscope with a pair of 0.58 N.A. A 15X reflecting Cassegrains to avoid possible aberrations in the NIR region.…”

Section: Characterizationmentioning

confidence: 99%

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Determination of Chemical Homogeneity of Fire Retardant Polymeric Nanocomposite Materials by Near-Infrared Multispectral Imaging Microscopy

et al. 2010

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“…In this case, the investigation of nanostructural size and the synergistic effect of various materials with different optical limiting mechanisms becomes a significant step toward the development of practical components and devices. − However, the integration of multiscale and multicomponent materials into an identical film generally has serious problems with compatibility and film-forming for use of both small molecules and nano-objects. As one of the most successful methods, electrostatic assembly , (Supporting Information) can lead to low loading weight percent of nano-objects and low energy transfer efficiency . In the past decade, we have developed electrochemically covalent assembly − for high loading integrations of multiscale and multicomponent building blocks with versatile function and distribution controllability.…”

Section: Introductionmentioning

confidence: 99%

Tuning Optical Limiting of Heterosized AuNPs and Fullerene by Countable Electrochemical Assembly

Zhang

et al. 2018

ACS Omega

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Tuning optical limiting was achieved based on the nanostructural and synergistic effects of heterosized gold nanoparticles and fullerene on electrochemical assembly. In particular, with thicknesses of 200, 1, and 10 nm, heterosized AuNP multilayers with periodical pairs of layers present a superior threshold of 0.59 J cm –2 to monosized AuNP films with the values of 0.89–2.55 J cm –2 , which was further significantly enhanced by the introduction of C 70 with a significant threshold drop from 0.43 to 0.13 J cm –2 , indicating that the reverse saturable absorption of C 70 had a key contribution compared to the free carrier absorption of AuNPs. This paper not only demonstrates that the hybrid engineering of heterosized AuNPs into an identical film is an effective way to enhance the optical limiting but also indicates that the reverse saturable absorption of C 70 is superior to free carrier absorption of AuNPs in optical limiting in AuNPs and C 70 hybrid films.

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Molecular State and Distribution of Fullerenes Entrapped in Sol−Gel Samples

Cited by 9 publications

References 37 publications

A new cyanoaromatic photosensitizer vs. 9,10-dicyanoanthracene: systematic comparison of the photophysical properties

A new cyanoaromatic photosensitizer vs. 9,10-dicyanoanthracene: systematic comparison of the photophysical properties

Determination of Chemical Homogeneity of Fire Retardant Polymeric Nanocomposite Materials by Near-Infrared Multispectral Imaging Microscopy

Tuning Optical Limiting of Heterosized AuNPs and Fullerene by Countable Electrochemical Assembly

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