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The fine-tuning of photoluminescence color of cadmium selenide (CdSe) nanoparticles by size-selective photoetching technique is reported. The results have shown that the photoluminescence enhanced significantly with the photoetching of CdSe and blue-shifted with a decrease in the wavelength used for the photoetching.

Silica-coated cadmium sulfide nanoparticles (SiO2/CdS) having a jingle-bell structure were prepared via size-selective photoetching and were used as photocatalysts for dehydrogenation of methanol. Irradiation of SiO2/CdS suspended in an aqueous solution containing methanol induced the liberation of hydrogen (H2), the amount of which increased linearly with increase in the time of irradiation.

The results of treatment of surface silanol groups with hydrophilic compounds, which enables silica-coated cadmium sulfide nanoparticles dissolved in water/methanol mixture, are examined. The resulting void space like the structure of a jingle-bell is also examined.

It has been possible to prepare CdS nanoparticle chains with line widths equal to the size of nanoparticles. A template was created by using the electrostatic interaction between the cationic surface modifiers on the CdS nanoparticles and the phosphate groups in DNA double strands.

Loading TiO2 particles on adsorbents significantly enhances the reaction rate of photoinduced mineralization of the typical herbicide propyzamide with the TiO2 photocatalyst. This was the result of an investigation of photodecomposition in aqueous solution of propyzamide, using naked TiO2 and TiO2-loaded adsorbent supports as photocatalysts. Aside from enhancing the rate of mineralization, the use of adsorbent supports was also found to reduce the concentration of solution-phase intermediates.

A study was done on the structure of capped semiconductor surfaces in atomic scale by fitting the experimentally obtained chemical compositions to those expected from modeled surfaces of capped semiconductors. Results show that differences in surface structures influence the photochemical and photoelectrochemical properties of capped PbS crystals. In addition, it was theorized that capped ArSH may function as mediators in the oxidation of some chemical species in solution.

The facile synthesis of highly luminescent ZnS-AgIn[S.sub.2] solid solution nanoparticles with no toxic elements is presented. These particles can be easily used as photocatalysts and quantum-dot solar cells.

Electric-field-induced changes in absorption and emission spectra of colloidal CdS nanoparticles ranging in size from 1.0 to 5.0 nm in diameter is measured by using electric field modulation spectroscopy. Results reveal that the emission intensity of CdS nanoparticles increases under the UV light irradiation in air and decreases in a vacuum condition and that fluorescence lifetime in the former case is longer than that in the latter.

The wavelength range available for the preparation of monodisperse CdS nanoparticles by the size-selective photoetching technique is investigated. The light of the CdS nanoparticle decreases with a decrease in the wavelength of irradiation light and finally reaches the smallest size of about 1.7nm with the monochromatic light irradiation at 365nm.

The use of size-selective photoetching technique to modify the core size after preparing CdS nanoparticles is described. It is revealed that the resulting particles have an adjustable void space inside the silica shell.