Fluorescence quenching processes of poly[2-methoxy-5-(2’ethyl-hexoxy)-p-phenylene vinylene] (MEH-PPV) in solution by electron acceptors, O2 and acid, have been studied. Static quenching of the fluorescence fromMEH-PP...Fluorescence quenching processes of poly[2-methoxy-5-(2’ethyl-hexoxy)-p-phenylene vinylene] (MEH-PPV) in solution by electron acceptors, O2 and acid, have been studied. Static quenching of the fluorescence fromMEH-PPV by an electron acceptor (DDQ or TCNE) occurs due to electron transfer from MEH-PPV to the electron acceptor and this electron transfer quenching can be promoted by chloroform. Photooxidation takes place in the MEH-PPV solution and singlet oxygen is an intermediate in the photooxidation, according to the results of ESR spectroscopy. Acid also plays an important role in the fluorescence quenching process of MEH-PPV, by the proto-nation of the alkoxy groups in the molecular chain.展开更多
6-Phenyl-2,2'-bipyridine linked pyrene and anthracene were synthesized and their photophysical properties were measured in different solvents with different polarity. 4-Pyren-1""-yl-6-phenyl-2,2'-bip...6-Phenyl-2,2'-bipyridine linked pyrene and anthracene were synthesized and their photophysical properties were measured in different solvents with different polarity. 4-Pyren-1""-yl-6-phenyl-2,2'-bipyridine (Ppbpy) showed significant solvent-dependent properities while 4-anthracen-yl-9""-yl-6-phenyl-2,2'-bipyridine (Apbpy) displayed solvent-independence, although they had similar molecular structure. Because of different twist angle between thyarene and aryl-bipyridine, Ppbpy displayed intermixing behaviors of local excited state (^1La and ^1Lb) and intramolecular charge transfer (ICT), but Apbpy only showed the properties of local excited state ^1La.展开更多
基金the National Natural Science Foundation of China (No. 20173066) and the Major State Basic Research Development Program of China (No. G2000078100).
文摘Fluorescence quenching processes of poly[2-methoxy-5-(2’ethyl-hexoxy)-p-phenylene vinylene] (MEH-PPV) in solution by electron acceptors, O2 and acid, have been studied. Static quenching of the fluorescence fromMEH-PPV by an electron acceptor (DDQ or TCNE) occurs due to electron transfer from MEH-PPV to the electron acceptor and this electron transfer quenching can be promoted by chloroform. Photooxidation takes place in the MEH-PPV solution and singlet oxygen is an intermediate in the photooxidation, according to the results of ESR spectroscopy. Acid also plays an important role in the fluorescence quenching process of MEH-PPV, by the proto-nation of the alkoxy groups in the molecular chain.
文摘6-Phenyl-2,2'-bipyridine linked pyrene and anthracene were synthesized and their photophysical properties were measured in different solvents with different polarity. 4-Pyren-1""-yl-6-phenyl-2,2'-bipyridine (Ppbpy) showed significant solvent-dependent properities while 4-anthracen-yl-9""-yl-6-phenyl-2,2'-bipyridine (Apbpy) displayed solvent-independence, although they had similar molecular structure. Because of different twist angle between thyarene and aryl-bipyridine, Ppbpy displayed intermixing behaviors of local excited state (^1La and ^1Lb) and intramolecular charge transfer (ICT), but Apbpy only showed the properties of local excited state ^1La.
