Photochemistry of colloidal semiconductors. 31. Preparation and photolysis of CdS sols in organic solvents

Journal Article · Thu Jul 13 00:00:00 EDT 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100351a049· OSTI ID:6972488

Fischer, C H; Henglein, A ^[1]

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1. Hahn-Meitner-Institut Berlin GmbH (Germany, F.R.)

CdS was prepared by adding hydrogen sulfide to a solution containing about 10{sup {minus}4} M Cd(ClO{sub 4}){sub 2} and various long-chain alkanethiols in tetrahydrofuran. With increasing thiol concentration smaller CdS particles were formed. Their absorption and fluorescence spectra were blue-shifted with decreasing particle size. The mean diameter, d (nm), of the particles depended on the thiol concentration, c (M), according to the relation log d = 1.32 - 0.13 log c. The colloids have remarkable stability: reflux heating (60{degree}C) and removal of the solvent and excess thiol (90{degree}C) did not affect them substantially. The separated particles could be redissolved to a large extent in organic solvents, such as cyclohexane, benzene, carbon tetrachloride, chloroform, and dichloromethane. Photolysis in the presence of oxygen led to smaller particles and finally to dissolution of the colloid. In the absence of oxygen larger particles were formed. In both cases the disulfide from the thiol used was produced, although the latter did not absorb at the wavelengths of the photolyzing light. A mechanism for these photolysis effects is discussed.

• OSTI ID: 6972488
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 93:14; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500 -- Photochemistry
CADMIUM COMPOUNDS
CADMIUM SULFIDES
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
COLLOIDS
DATA
DECOMPOSITION
DISPERSIONS
EXPERIMENTAL DATA
INFORMATION
INORGANIC PHOSPHORS
MATERIALS
MEASURING INSTRUMENTS
MEASURING METHODS
NUMERICAL DATA
PHOSPHORS
PHOTOCHEMICAL REACTIONS
PHOTOCHEMISTRY
PHOTOLYSIS
SEMICONDUCTOR MATERIALS
SOLS
SULFIDES
SULFUR COMPOUNDS
SYNTHESIS