Photosensitization of quantum-size TiO[sub 2] particles in water-in-oil microemulsions

Journal Article · Thu Aug 04 04:00:00 EDT 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100082a039· OSTI ID:6994437

Joselevich, E; Willner, I ^[1]

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1. Hebrew Univ., Jerusalem (Israel)

Ultrasmall TiO[sub 2] particles (2R = 9.0 [+-] 0.5 A) were generated in situ in a water-in-oil (w/o) microemulsion composed of water, cetyldimethylbenzylammonium chloride ICDBA, and benzene, by controlled hydrolysis of TiCl[sub 4]. Effective photosensitization of the TiO[sub 2] particles by Ru(II) tris(bipyridine), Ru(bpy)[sub 3][sup 2+], proceeds in the w/o microemulsion. The photosensitization of TiO[sub 2] was studied by following the emission decay of excited Ru(bpy)[sub 3][sup 2+] at different TiO[sub 2] concentrations. The emission decay curves of excited Ru(bpy)[sub 3][sup 2+] were analyzed by assuming a Poisson distribution of the TiO[sub 2] particles over the reverse micelles and realizing that excited Ru(bpy)[sub 3][sup 2+] photosensitizes TiO[sub 2] by two photosensitization pathways: (a) intramicellar electron injection quenching (k[sub q]) and (b) particle incorporation by intermicellar exchange (k[sub c]) followed by fast intramicellar quenching. The derived values of intramicellar electron injection and intermicellar exchange rate constants were k[sub q] = 7 x 10[sup 6] s[sup [minus]1] and 1.4 x 10[sup 9] M[sup [minus]1] s[sup [minus]1], respectively. 42 refs., 11 figs., 1 tab.

• OSTI ID: 6994437
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 98:31; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

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ABSORPTION SPECTRA
AMMONIUM COMPOUNDS
AROMATICS
BENZENE
CHALCOGENIDES
CHEMICAL REACTIONS
CHLORINE COMPOUNDS
COLLOIDS
COMPLEXES
DECOMPOSITION
DISPERSIONS
EMULSIONS
ENERGY
ENERGY SOURCES
HALOGEN COMPOUNDS
HYDROCARBONS
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
HYDROLYSIS
INORGANIC ACIDS
LYSIS
MATHEMATICAL MODELS
MICROEMULSIONS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOSENSITIVITY
RENEWABLE ENERGY SOURCES
RUTHENIUM COMPLEXES
SENSITIVITY
SOLAR ENERGY
SOLID CLUSTERS
SOLVOLYSIS
SPECTRA
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPLEXES
TRANSITION ELEMENT COMPOUNDS
WATER