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Indexed by:期刊论文

Date of Publication:2018-10-18

Journal:JOURNAL OF PHYSICAL CHEMISTRY C

Included Journals:EI、SCIE

Volume:122

Issue:41

Page Number:23321-23328

ISSN No.:1932-7447

Abstract:The ultrafast transient dynamics of a free-base tetraphenylporphyrin (H2TPP) surface-mounted metal organic framework (SURMOF) is spectroscopically characterized and compared with that of H2TPP in ethanol solution. A dramatic increase of the quantum yield of the Soret band fluorescence (S-2 -> S-0) is observed in the H2TPP-SURMOF, which is accompanied by an increase of the S-2 fluorescence lifetime and a broadening of the fluorescence spectra. In contrast, the Q band (S-1) fluorescence is strongly quenched in the H2TPP SURMOF compared with the fluorescence of H(2)TPPin ethanol solution. The observed transient absorption kinetics supports the fluorescence data. The enhanced fluorescence in the SURMOF compared with H2TPP in solution is attributed to the combination of two factors: the alignment of the vibrational energy levels of the dominant Franck-Condon active mode of the Soret and Q bands and the weaker coupling of these modes to the environment.