Photochemistry and radiation chemistry of colloidal semiconductors. 12. Intermediates of the oxidation of extremely small particles of CdS, ZnS, and Cd/sub 3/P/sub 2/ and size quantization effects (a pulse radiolysis study)
The reactions of hydroxyl radicals with colloidal Q-CdS, Q-ZnS, and Q-Cd/sub 3/P/sub 2/ (materials of extremely small particle size showing optical size quantization effects) were studied pulse radiolytically. The radicals attack the particles at diffusion-controlled rates. In all three cases, a product with a broad absorption band in the visible (sulfides) or near-infrared (phosphide) is formed. This band shifts to shorter wavelengths with decreasing particle size (size quantization effect). It is attributed to surface trapped holes. These holes react with dissolved oxygen. The colloidal particles become a little smaller by OH attack. With use of a CdS sample with a structured absorption spectrum, it is shown that the product particles have their absorption maxima at slightly shorter wavelengths than the reactant particles (size quantization effect). 18 references, 7 figures, 1 table.
- Research Organization:
- Hahn-Meitner-Institut fuer Kernforschung Berlin, West Germany
- OSTI ID:
- 5825969
- Journal Information:
- J. Am. Chem. Soc.; (United States), Vol. 108:3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Photochemistry and radiation chemistry of semiconductor colloids. 27. Preparation of colloidal PbO sub 2 various electron-transfer processes
Photochemistry of semiconductor colloids. 22. Electron injection from illuminated CdS into attached TiO/sub 2/ and ZnO particles
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
CADMIUM PHOSPHIDES
OXIDATION
PHOTOCHEMICAL REACTIONS
CADMIUM SULFIDES
HYDROXYL RADICALS
ZINC SULFIDES
ABSORPTION SPECTROSCOPY
COLLOIDS
DIFFUSION
EXPERIMENTAL DATA
HALF-LIFE
PARTICLE SIZE
PULSE TECHNIQUES
RADIOLYSIS
REACTION INTERMEDIATES
SEMICONDUCTOR MATERIALS
CADMIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
DATA
DECOMPOSITION
DISPERSIONS
INFORMATION
INORGANIC PHOSPHORS
MATERIALS
NUMERICAL DATA
PHOSPHIDES
PHOSPHORS
PHOSPHORUS COMPOUNDS
PNICTIDES
RADIATION CHEMISTRY
RADIATION EFFECTS
RADICALS
SIZE
SPECTROSCOPY
SULFIDES
SULFUR COMPOUNDS
ZINC COMPOUNDS
400500* - Photochemistry
400600 - Radiation Chemistry