TY - JOUR

T1 - Steady state and time resolved fluorescence studies of azadioxatriangulenium (ADOTA) fluorophore in silica and PVA thin films

AU - Chib, Rahul

AU - Raut, Sangram

AU - Shah, Sunil

AU - Grobelna, Beata

AU - Akopova, Irina

AU - Rich, Ryan

AU - Sørensen, Thomas Just

AU - Laursen, Bo W.

AU - Grajek, Hanna

AU - Gryczynski, Zygmunt

AU - Gryczynski, Ignacy

PY - 2015

Y1 - 2015

N2 - A cationic azadioxatriangulenium dye was entrapped in silica thin films obtained by the sol-gel process and in poly (vinyl) alcohol (PVA) thin films. Azadioxatriangulenium is a red emitting fluorophore with a long fluorescence lifetime of ∼20 ns. The fluorescent properties of azadioxatriangulenium in silica thin films and PVA films were studied by means of steady-state and time resolved fluorescence techniques. We have found that the azadioxatriangulenium entrapped in silica thin film has a wider fluorescence lifetime distribution (Lorentzian distribution), lower fluorescence efficiencies, shorter lifetimes compared to Azadioxatriangulenium in a PVA film. The local environment of azadioxatriangulenium molecules in the silica thin film is rich with water and ethanol, which creates the possibility of forming excited state aggregates due to high concentration of dye within a small confined area. In contrast to the PVA matrices, the porous silica films allow restricted rotations of Azadioxatriangulenium molecules, which result in faster and complex fluorescence anisotropy decays suggesting energy migration among dye molecules.

AB - A cationic azadioxatriangulenium dye was entrapped in silica thin films obtained by the sol-gel process and in poly (vinyl) alcohol (PVA) thin films. Azadioxatriangulenium is a red emitting fluorophore with a long fluorescence lifetime of ∼20 ns. The fluorescent properties of azadioxatriangulenium in silica thin films and PVA films were studied by means of steady-state and time resolved fluorescence techniques. We have found that the azadioxatriangulenium entrapped in silica thin film has a wider fluorescence lifetime distribution (Lorentzian distribution), lower fluorescence efficiencies, shorter lifetimes compared to Azadioxatriangulenium in a PVA film. The local environment of azadioxatriangulenium molecules in the silica thin film is rich with water and ethanol, which creates the possibility of forming excited state aggregates due to high concentration of dye within a small confined area. In contrast to the PVA matrices, the porous silica films allow restricted rotations of Azadioxatriangulenium molecules, which result in faster and complex fluorescence anisotropy decays suggesting energy migration among dye molecules.

KW - Aggregation

KW - Azadioxatriangulenium

KW - Fluorophore

KW - Lorentzian lifetime distribution

KW - Luminescence

KW - Sol-gel process

U2 - 10.1016/j.dyepig.2015.01.027

DO - 10.1016/j.dyepig.2015.01.027

M3 - Journal article

C2 - 26594075

AN - SCOPUS:84922896033

VL - 117

SP - 16

EP - 23

JO - Dyes and Pigments

JF - Dyes and Pigments

SN - 0143-7208

ER -