Photoinduced charge separation across the solid-liquid interface of porous sol-gel glasses: Catalyzed hydrogen generation from water

Journal Article · Thu Nov 02 00:00:00 EST 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100359a004· OSTI ID:6751589

Slama-Schwok, A; Avnir, D; Ottolenghi, M ^[1]

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1. Hebrew Univ. of Jerusalem (Israel)

Photoinduced electron transfer between (Ir(bpy){sub 2}(C{sup 3},N{prime})bpy){sup 3+}, Ir(III), trapped in a porous silica glass generated by the sol-gel process, and 1,4-dimethoxybenzene (DMB) dissolved in a water phase in the pores of the glass, was observed. The kinetics of the redox reactions associated with the Ir(II) + DMB{sup +} radical ion pair were studied at different pH and ionic strength values. A retardation of 4 orders of magnitude of the back-electron-transfer process, with respect to homogeneous solutions, was observed at neutral pH for {approx} 25% of the generated Ir(II). The effect is attributed to the immobilization of Ir(II) by trapping in the glass matrix and of DMB{sup +} by adsorption on the pores surface. At acidic pH, retardation of the back-reaction leads to catalyzed hydrogen generation from water.

• OSTI ID: 6751589
• Journal Information: Journal of Physical Chemistry; (USA), Vol. 93:22; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
08 HYDROGEN
SOL-GEL PROCESS
HYDROGEN PRODUCTION
DATA ANALYSIS
ELECTRON TRANSFER
EXPERIMENTAL DATA
IRIDIUM
MEASURING INSTRUMENTS
MEASURING METHODS
PHOTOSYNTHESIS
WATER
CHEMICAL REACTIONS
DATA
ELEMENTS
HYDROGEN COMPOUNDS
INFORMATION
METALS
NUMERICAL DATA
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PLATINUM METALS
SYNTHESIS
TRANSITION ELEMENTS
400201* - Chemical & Physicochemical Properties
360104 - Metals & Alloys- Physical Properties
080100 - Hydrogen- Production