Phototransformation of anthraquinone-2-sulphonate in aqueous solution

摘要: Anthraquinone-2-sulphonate (AQ2S) is a triplet sensitiser that has recently been used to model the photoreactivity of chromophoric dissolved organic matter (CDOM). We show photolysis quantum yield AQ2S under UVA irradiation varies from (3.4 ± 0.2) × 10−3 at μM levels (1.8 0.1) 10−2 3 mM (μ σ). This trend consistent with combination direct phototransformation and transformation sensitised by photogenerated reactive species. In both cases transient water adduct would be involved. Depending on initial quinone concentration, could undergo transformation, give back ground-state or react it. The prevalence latter process high concentration account for increased values yield. When using as sensitiser, one should not exceed an 0.1 mM. Under conditions negligible compared photolysis, providing simpler system studied, independent concentration. paper also shows, adoption density functional theory calculations, state most spin localised CO, analogous other photoactive quinones, which accounts oxidising character tends reduced semiquinone radical.