Figure 2.
Quenching of 1O2 phosphorescence by TBBPA in MeCN. A: Observed first order rate constants for 1O2 quenching as a function of TBBPA concentration. The plot was approximated by two linear fittings: Line 1, a TBBPA monomer region yielding kq = (6.1 ± 0.5) × 105 M-1 s-1. Line, 2 a TBBPA dimer/aggregate region yielding kq = (2.9 ± 0.3) × 104 M-1 s-1. Inset B: Examples of 1O2 phosphorescence decay (1-4) in the presence of increasing TBBPA concentrations (0 mM, 15 mM, 45 mM, 135 mM). Perinaphthenone was used as a 1O2 photosensitizer excited at 355 nm.