Single-photon ionization of pyrene and anthracene giving trapped electrons in alkali-metal-cation-exchanged zeolites X and Y. A direct time-resolved diffuse reflectance study

Journal Article · Thu Jan 24 04:00:00 EST 1991 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100155a002· OSTI ID:5761005

Iu, Kai-Kong; Thomas, J K ^[1]

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1. Univ. of Notre Dame, IN (USA)

Time-resolved diffuse reflectance spectroscopy is used to investigate the photolysis of anthracene- or pyrene-impregnated alkali-metal-cation-exchanged zeolite X and Y with a nitrogen laser (337 nm). The studies suggest that anthracene or pyrene molecules are distributed in at least two different sites (active and nonactive) in the zeolite X and Y. Excitation of anthracene or pyrene adsorbed in nonactive sites produces singlet excited states of anthracene or pyrene, which can either be photoionized by absorbing a second photon or decay to the triplet excited states through intersystem crossing; however, anthracene or pyrene adsorbed in active sites is photoionized through a single-photon process. The products of the photoionization are cation radicals of arene and trapped electrons (e.g., Na{sub 4}{sup 3+} for NaY). The broad absorption band for the trapped electron is around 550 nm for both NaX and NaY; around 620 nm for both LiX and LiY and around 710 nm for KX.

• OSTI ID: 5761005
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 95:2; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ABSORPTION SPECTROSCOPY
ANTHRACENE
AROMATICS
CHEMICAL REACTIONS
CONDENSED AROMATICS
DATA
DECOMPOSITION
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
IONIZATION
LASERS
MATERIALS
MEASURING METHODS
MINERALS
NUMERICAL DATA
ORGANIC COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOIONIZATION
PHOTOLYSIS
PYRENE
SPECTROSCOPY
SURFACE PROPERTIES
ZEOLITES