Photoinduced Electron Transfer Reactions of Water Soluble Porphyrins in Zeolite Environment
نویسندگان
چکیده
Excited state interactions of zeolite adsorbed porphyrins have been investigated by steady luminescence quenching technique with certain antioxidants such as reduced glutathione, ascorbic acid and L-cysteine. The supported porphyrins, meso-tetra (N-methyl-4-pyridyl) porphyrin (H2TMPyP4+) zinc tetra(N-methyl-4-pyridyl) (ZnTMPyP4+) were prepared characterized various techniques Diffuse Reflectance Spectra (DRS), Scanning Electron Microscope (SEM), powder X-Ray Diffraction (XRD) BET surface area. interaction zeolites are shown to increase the lifetime singlet excited decays biphasic in nature. splitting emission band occurs 1:1 glycerol: water solution due changes dielectric solvation sphere associated porphyrin. Stern-Volmer plots I0/I vs quencher concentration [Q] linear whole range used. These studies revealed effective for compared free base effect quenchers acidity has also studied rate constant (kq) is found order 109 M−1 s−1. reaction obeys Rehm-Weller Equation be thermodynamically favoured electron transfer from (reductive quenching).
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ژورنال
عنوان ژورنال: Journal of Fluorescence
سال: 2021
ISSN: ['1053-0509', '1573-4994']
DOI: https://doi.org/10.1007/s10895-021-02747-8