Andrasik Stephen J, Belfield Kevin D, Bondar Mykhailo V, Hernandez Florencio E, Morales Alma R, Przhonska Olga V, Yao Sheng
Department of Chemistry and CREOL, College of Optics and Photonics, University of Central Florida, P.O. Box 162366, Orlando, FL 32816-2366, USA.
Chemphyschem. 2007 Feb 19;8(3):399-404. doi: 10.1002/cphc.200600568.
The spectral properties of new fluorene-based photosensitizers for efficient singlet oxygen production are investigated at room temperature and 77 K. Two-photon absorption (2PA) cross-sections of the fluorene derivatives are measured by the open aperture Z-scan method. The quantum yields of singlet oxygen generation under one- and two-photon excitation (phi(delta) and 2PAphi(delta), respectively), are determined by the direct measurement of singlet oxygen luminescence at approximately 1270 nm. The values of phi(delta) are independent of excitation wavelength, ranging from 0.6-0.9. The singlet oxygen quantum yields under two-photon excitation are 2PAphi(delta) approximately 1/2 phi(delta), indicating that the two processes exhibit the same mechanism of singlet oxygen production, independent of the mechanism of photon absorption.
在室温及77 K下研究了用于高效产生单线态氧的新型芴基光敏剂的光谱特性。通过开孔Z扫描法测量芴衍生物的双光子吸收（2PA）截面。通过直接测量约1270 nm处的单线态氧发光来确定单光子和双光子激发下的单线态氧产生量子产率（分别为φ(δ)和2PAφ(δ)）。φ(δ)的值与激发波长无关，范围为0.6 - 0.9。双光子激发下的单线态氧量子产率为2PAφ(δ)≈1/2φ(δ)，表明这两个过程表现出相同的单线态氧产生机制，与光子吸收机制无关。
