A novel optical oxygen sensing system based on triplet–triplet reflectance of fullerene C60-polystyrene film by time-resolved spectroscopy using diffuse reflectance laser flash photolysis
Abstract
A new optical oxygen sensing system based on the triplet lifetimes of C60 in polystyrene (PS) film under different oxygen concentrations was developed by using OPO–Nd–YAG laser flash photolysis. The lifetime of the photoexcited triplet state of C60–PS film decreases with increasing oxygen concentration, indicating that the photoexcited triplet state of C60 in the PS film was quenched effectively by oxygen. A Stern–Volmer plot of C60 in PS film exhibits considerable linearity (r2 = 0.999), Ksv is estimated to be 0.50 %−1. The quenching rate constant for the photoexcited triplet state of C60 in the PS film by oxygen, kq, is 5.0 × 103 %−1 s−1. A highly sensitive oxygen sensor based on the photoexcited triplet state of C60 molecules by oxygen has been developed using time-resolved spectroscopy with laser flash photolysis.