A composite sol–gel/fluoropolymer matrix for dissolved oxygen optical sensing

A thin film dissolved oxygen optical sensor was fabricated by encapsulating the phosphorescent dye erythrosin B in a sol–gel/fluoropolymer composite matrix. Strong phosphorescence, which was efficiently quenched by dissolved oxygen, was observed. The sensor was stable, optically transparent, resistant to contamination, with good mechanical properties. Fast response, coupled with good sensitivity and resistance to leaching, were also exhibited by this system. The Stern–Volmer (SV) plot was linear at low dissolved oxygen concentrations, but exhibited marked upward turning at higher concentrations due to combined dynamic and static quenching processes.