Development of Dissolved Oxygen Sensor Based on Time‐domain Lifetime Measurement with a Sensing Film Fabricated by Embedding PtOEP in Highly Stable and Highly Hydrophobic Fluorinated Matrix

Abstract A dissolved oxygen sensor was developed based on time‐domain lifetime measurement with an oxygen sensing film. The oxygen sensing film was fabricated by embedding PtOEP in a highly stable and highly hydrophobic fluorinated matrix synthesized from methacrylate, fluorinated methacrylate, and 3‐(tris(trimethylsilyloxy)silyl)propyl methacrylate via free radical polymerization. The fluorinated methacrylate provided the high stability and the 3‐(tris(trimethylsilyloxy)silyl)propyl methacrylate provided the extra hydrophobicity. The PtOEP was excited using pulsed signals from a green‐light LED and the fluorescence lifetime was evaluated by time‐domain lifetime measurement. The dynamical quenching of fluorescence response by dissolved oxygen was calibrated using the Stern‐Volmer plot with a high ratio of 5.68 and a Stern‐Volmer constant of 0.112 mg −1 dm 3 . It was demonstrated that the dissolved oxygen sensing film showed high stability under the varied excitation intensity and long‐term stability in the accelerated aging experiment and the repeated freeze‐thaw‐cycling tests.