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An optical oxygen sensor based on the photoluminescent quenching of palladium porphyrin with long alkyl chain, palladium 5-(4-undecancarboxylpyridyl)-10,15,20-tritolylporphyrin (PdPC10COOH), a self-assembled film on an alumina plate has been developed. The luminescence intensity of the PdPC10COOH film decreased with increasing oxygen pressure. The ratio I₀/I₁₀₀ as a sensitivity measure of the sensing film is very large, indicating that this film is a highly sensitive device for oxygen pressure. The response times of the sensor are 26 s on going from argon to oxygen and 131 s on going from oxygen to argon.

An optical oxygen sensor based on the phosphorescence quenching of palladium tetrakis(4-carboxyphenyl)porphyrin (PdTCPP) self-assembled film (SAM) on alumina plate was developed. The phosphorescence intensity of PdTCPP film decreased with increasing oxygen pressure, indicating that the film can be used as an optical oxygen-sensing device based on phosphorescence quenching by oxygen. The ratio I₀/I₁₀₀ as a sensitivity measure of the sensing film is estimated to be 17.7, showing that the film is a highly sensitive device for oxygen pressure. The film obeyed Stern–Volmer plots with a multisite model and possessed good operational stability and a fast response. Response times are 36 s for deoxygenated to oxygenated conditions and 148 s for the reverse conditions.

Optical oxygen-sensing systems based on the quenching of the photoexcited triplet state of platinum porphyrins—platinum octaethylporphyrin (PtOEP) and platinum tetrakis(pentafluorophenyl)porphyrin (PtTFPP)—in polystyrene (PS) using two different time-resolved spectroscopies (luminescence lifetime measurement and diffuse reflectance laser flash photolysis) have been developed. Using both spectroscopies, the same values of Stern-Volmer constant K_SV and quenching rate constant k_q (K_SV = k_qτ₀) are obtained. The decays of the luminescence and triplet-triplet reflectance of the platinum porphyrins in PS consisted of two components (faster and slower lifetimes) in the absence and presence of oxygen. For both faster and slower components the lifetime decreases with increasing oxygen concentration. For both components a Stern-Volmer plot of the platinum porphyrin-PS films exhibits linearity. However, k_q of the faster component is larger than that of the slower component (for PtOEP, three times larger; for PtTFPP, 40 times larger), indicating that two different oxygen-accessible sites exist in the platinum porphyrin-PS films. The faster and slower components are related to oxygen-accessible sites on the surface and in the bulk of the platinum porphyrin films respectively. Concerning the fractional contributions of each lifetime component, the contribution of the faster component is greater than that of the slower component, indicating that the sensing site on the surface is important for optical sensing. The contribution of different oxygen-accessible sites in platinum porphyrin-PS films for oxygen sensing is clarified by these techniques.

A series of new fluoropolymer, poly(styrene-co-trifluoroethylmethacrylate) (poly-Sty_n-co-TFEM_m), with different composition ratios of Sty and TFEM units, is synthesized and applied to the matrix of an optical oxygen sensing probe using phosphorescence quenching of metalloporphyrins, platinum and palladium octaethylporphyrin (PtOEP and PdOEP), by oxygen. The phosphorescence intensity of PtOEP and PdOEP in poly-Sty_n-co-TFEM_m film decreased with increase of oxygen concentration. The ratio I₀/I₁₀₀ is used as a sensitivity of the sensing film, where I₀ and I₁₀₀ represent the detected phosphorescence intensities from a film exposed to 100% argon and 100% oxygen, respectively. For PtOEP in poly-Sty_n-co-TFEM_m film, I₀/I₁₀₀ ratios are more than 20.6 and large Stern–Volmer constants greater than 0.49%^-1 are obtained compared with PtOEP in PS film. For PdOEP in poly-Sty_n-co-TFEM_m film, on the other hand, large I₀/I₁₀₀ values greater than 188.7 are obtained. In both cases for PtOEP and PdOEP, I₀/I₁₀₀ values increased with increase of the number of TFEM units in poly-Sty_n-co-TFEM_m. The response times of PtOEP and PdOEP immobilized in poly-Sty₁-co-TFEM_2.50 films are 5.5 and 3.0 s on going from argon to oxygen and 90.0 and 143 s from oxygen to argon, respectively. These results show that PtOEP and PdOEP immobilized in poly-Sty_n-co-TFEM_m films are highly sensitive devices for oxygen.