TY - JOUR
T1 - Oxygen sensing based on lifetime of photoexcited triplet state of platinum porphyrin-polystyrene film using time-resolved spectroscopy
AU - Amao, Yutaka
AU - Asai, Keisuke
AU - Okura, Ichiro
N1 - Funding Information:
This work was partially supported by a Grant-in-Aid for Scientific Research on Priority Areas Research from the Ministry of Education, Science, Sports, and Culture of Japan (10145211).
PY - 2000
Y1 - 2000
N2 - 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(qθO)) 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. Copyright (C) 2000 John Wiley and Sons, Ltd.
AB - 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(qθO)) 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. Copyright (C) 2000 John Wiley and Sons, Ltd.
KW - Laser flash photolysis
KW - Luminescence lifetime
KW - Optical oxygen sensing
KW - Platinum porphyrin
KW - Stem-Volmer constant
KW - Time-resolved spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=0033657610&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033657610&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1099-1409(200004/05)4:3<292::AID-JPP216>3.0.CO;2-W
DO - 10.1002/(SICI)1099-1409(200004/05)4:3<292::AID-JPP216>3.0.CO;2-W
M3 - Article
AN - SCOPUS:0033657610
VL - 4
SP - 292
EP - 299
JO - Journal of Porphyrins and Phthalocyanines
JF - Journal of Porphyrins and Phthalocyanines
SN - 1088-4246
IS - 3
ER -