Photoeffects in thin-film molecular-level chromophore-quencher assemblies. 2. Photoelectrochemistry

Journal Article · Thu Jan 12 04:00:00 EST 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100338a061· OSTI ID:5360142

Surridge, N A; Hupp, J T; McClanahan, S F; Gould, S; Meyer, T J ^[1]

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1. Univ. of North Carolina, Chapel Hill (USA)

Photocurrents appear upon visible photolysis of thin films of chlorosulfonated polystyrene ((-CH{sub 2}CH(p-C{sub 6}H{sub 4}SO{sub 2}Cl)){sub x}-; PS-SO{sub 2}Cl) containing the chemically attached chromophore ((bpy){sub 2}Ru(5-NH{sub 2}phen))(PF{sub 6}){sub 2} (bpy is 2,2'-bipyridine, 5-NH{sub 2}phen is 5-amino-1,10-phenanthroline). The chemical attachment is by sulfonamide binding. The photocurrents arise following oxidative quenching of the metal-to-ligand charge-transfer excited state(s) of the complex by paraquat (PQ{sup 2+}) in the presence of the reductive scavenger TEOA, triethanolamine. A kinetic model has been derived that accounts for variations in photocurrent with light intensity and (PQ{sup 2+}) or (TEOA) in the external solution. Comparisons with earlier quenching studies obtained by laser flash photolysis show that only a fraction of the chromophores in the film contribute to the photocurrent. The efficiency of photocurrent production depends upon the concentration gradient of the chromophore. It rises initially as the chromophore content increases but falls dramatically in films where the chromophore has reached the electrode-film interface. Under maximal conditions the per photon absorbed quantum yield for photocurrent production reached the electrode-film interface. Under maximal conditions the per photon absorbed quantum yield for photocurrent production reached 0.14, 0.18 with 0.1 M isopropyl alcohol added.

• DOE Contract Number: FG05-86ER13633
• OSTI ID: 5360142
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 93:1; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
CHEMICAL REACTIONS
CURRENTS
DATA
DECOMPOSITION
ELECTRIC CURRENTS
ELECTROCHEMICAL CELLS
EQUIPMENT
EXPERIMENTAL DATA
FILMS
INFORMATION
MATERIALS
NUMERICAL DATA
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
ORGANIC SULFUR COMPOUNDS
PETROCHEMICALS
PETROLEUM PRODUCTS
PHOTOCHEMICAL REACTIONS
PHOTOCURRENTS
PHOTOELECTROCHEMICAL CELLS
PHOTOLYSIS
PLASTICS
POLYMERS
POLYOLEFINS
POLYSTYRENE
POLYVINYLS
SOLAR EQUIPMENT
SYNTHETIC MATERIALS
THIN FILMS