The effect of gold nanoparticles on exchange processes in collision complexes of triplet and singlet oxygen molecules with excited eosin molecules

Abstract

We have studied exchange processes in contact complexes of triplet eosin molecules with oxygen molecules in the triplet and singlet ( 1 Δ g ) states in thin polyvinylbutyral films in the presence of gold nanoparticles. Upon resonant excitation of surface plasmons in gold nanoparticles into the absorption band of eosin molecules-singlet oxygen sensitizers-we have obtained an increase in the intensity of the delayed fluorescence and an increase in the lifetime of the dye with simultaneous quenching of the luminescence of singlet oxygen. The kinetics of the delayed fluorescence of the dye as a result of singlet-triplet annihilation of triplet eosin molecules with singlet oxygen molecules has been investigated. To compare theoretical and experimental data, we have numerically simulated energy transfer processes. Rate constants of energy transfer and of singlet-triplet annihilation, as well as quenching constants of triplet states of the dye by molecular oxygen, have been calculated. Luminescence quantum yield 1 Δ g of polyvinylbutyral has been estimated. We have analyzed quantum-chemically electronic mechanisms of singlet-triplet annihilation of oxygen and eosin.

Photocatalytic Removal of Crystal Violet Dye Utilizing Greenly Synthesized Iron Oxide Nanoparticles

“…Under dark conditions, the highest decolorization percentage of the crystal violet dye was detected at a concentration of 1.0 mg/mL, and a relative decolorization percentage of 64.23% was recorded at a reaction time of 210 min (Figure 11D). In the presence of a photocatalyst, the generation of surface plasmons by the nanoparticles occurred via echoing stimulation through the molecular system [65]. Hence, the initiation of the dye degradation was facilitated by the creation of photonic stimulation by the nanoparticles [66].…”

Surface-enhanced Raman spectroscopy for antiplatelet therapy effectiveness assessment

“…The gold plate was placed in distilled water and AVESTA femtosecond laser unit with a TETA compressor (TETA Yb amplifier system) was used. Ablation procedure is described in detail in [24]. The energy and pulse duration of the laser beam at λ = 1032 nm were 15 µJ and 280 fs, respectively.…”

Динамика термолюминесценции при двойном лазерном Vis-IR возбуждении молекул эозина с кислородом и наночастицами серебра в пленке поливинилбутираля

“…Сравнивая константы тушения синглетных и триплетных состояний молекул красителя молекулярным кислородом, можно заметить, что эти значения различаются более чем на порядок и отражают стандартные процессы тушения молекул в конденсированных средах [22]. Ранее в работе [21] нами были подробно изучены кинетические и квантово-химические особенности реакции (3) синглеттриплетной аннигиляции молекул (T . .…”