Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrin

The kinetics of triplet state decay and concomitant delayed fluorescence of tetraphenylporphyrin (TPP) incorporated into the multilayers of n-decanol adsorbed on the external surface of zeolites at different temperatures were studied by the laser flash photolysis via monitoring the emission and diff...

Full description

Saved in:
Bibliographic Details
Main Authors: Peter P. Levin, Silvia M. B. Costa
Format: Article
Language:English
Published: Wiley 2002-01-01
Series:International Journal of Photoenergy
Online Access:http://dx.doi.org/10.1155/S1110662X02000193
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849305190381912064
author Peter P. Levin
Silvia M. B. Costa
author_facet Peter P. Levin
Silvia M. B. Costa
author_sort Peter P. Levin
collection DOAJ
description The kinetics of triplet state decay and concomitant delayed fluorescence of tetraphenylporphyrin (TPP) incorporated into the multilayers of n-decanol adsorbed on the external surface of zeolites at different temperatures were studied by the laser flash photolysis via monitoring the emission and diffuse-reflectance. In deoxygenated samples, the kinetics of diffusion-controlled bimolecular triplet-triplet annihilation (TTA) has been used to probe the multilayers. A very large local concentration of reactants may be obtained using small bulk amounts. A fast TTA rate constant demonstrated the triplet energy migration in TPP assemblies formed at the liquid/solid interface. The TTA in aerated samples is mediated by molecular oxygen leading to 1O2 feedback—induced delayed fluorescence. Singlet oxygen works as an efficient mobile energy carrier between TPP triplets. The parameters of both TTA may be modified by multilayer, which acts as microreactor with supramolecular organization. The freezing of n-decanol results in dramatic apparent acceleration of both direct and 1O2 mediated TTA due to the increase in local TPP concentration because of displacement of TPP molecules into the residual liquid domains in polycrystalline matrix. The concentration of TPP in those microreactors can be three orders of magnitude larger than the solubility limit in a particular neat liquid solvent demonstrating the unique features of solid solution, which seems to be due to the presence of crystal/liquid interfaces.
format Article
id doaj-art-08304d942e9c44179060f74466ae1d2f
institution Kabale University
issn 1110-662X
language English
publishDate 2002-01-01
publisher Wiley
record_format Article
series International Journal of Photoenergy
spelling doaj-art-08304d942e9c44179060f74466ae1d2f2025-08-20T03:55:32ZengWileyInternational Journal of Photoenergy1110-662X2002-01-014416117110.1155/S1110662X02000193Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrinPeter P. Levin0Silvia M. B. Costa1Centro de Quimica Estrutural, Complexo 1, Instituto Superior Tecnico, Lisbon Codex 1096, PortugalCentro de Quimica Estrutural, Complexo 1, Instituto Superior Tecnico, Lisbon Codex 1096, PortugalThe kinetics of triplet state decay and concomitant delayed fluorescence of tetraphenylporphyrin (TPP) incorporated into the multilayers of n-decanol adsorbed on the external surface of zeolites at different temperatures were studied by the laser flash photolysis via monitoring the emission and diffuse-reflectance. In deoxygenated samples, the kinetics of diffusion-controlled bimolecular triplet-triplet annihilation (TTA) has been used to probe the multilayers. A very large local concentration of reactants may be obtained using small bulk amounts. A fast TTA rate constant demonstrated the triplet energy migration in TPP assemblies formed at the liquid/solid interface. The TTA in aerated samples is mediated by molecular oxygen leading to 1O2 feedback—induced delayed fluorescence. Singlet oxygen works as an efficient mobile energy carrier between TPP triplets. The parameters of both TTA may be modified by multilayer, which acts as microreactor with supramolecular organization. The freezing of n-decanol results in dramatic apparent acceleration of both direct and 1O2 mediated TTA due to the increase in local TPP concentration because of displacement of TPP molecules into the residual liquid domains in polycrystalline matrix. The concentration of TPP in those microreactors can be three orders of magnitude larger than the solubility limit in a particular neat liquid solvent demonstrating the unique features of solid solution, which seems to be due to the presence of crystal/liquid interfaces.http://dx.doi.org/10.1155/S1110662X02000193
spellingShingle Peter P. Levin
Silvia M. B. Costa
Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrin
International Journal of Photoenergy
title Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrin
title_full Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrin
title_fullStr Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrin
title_full_unstemmed Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrin
title_short Liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet-triplet annihilation of porphyrin
title_sort liquid and frozen multilayers of decanol in zeolites as microreactors for direct and oxygen mediated triplet triplet annihilation of porphyrin
url http://dx.doi.org/10.1155/S1110662X02000193
work_keys_str_mv AT peterplevin liquidandfrozenmultilayersofdecanolinzeolitesasmicroreactorsfordirectandoxygenmediatedtriplettripletannihilationofporphyrin
AT silviambcosta liquidandfrozenmultilayersofdecanolinzeolitesasmicroreactorsfordirectandoxygenmediatedtriplettripletannihilationofporphyrin