Highly luminescent CdS-core ZnS-shell nanorods stabilized by mercaptopropionic acid in water were synthesized wet-chemically and characterized by measuring photoluminescence spectra and kinetic profiles as well as absorption spectra, diffraction patterns, and electron microscope images. Photoluminescence from CdS nanorods 22 nm in diameter shifts to the blue by as much as 2.8 nm and increases as high as 1.8 times with the thickness of the passivating ZnS shell, whereas the luminescence lifetime of 1:1 CdS@ZnS coreshell nanorods is shorter by 1.6 times at 550 nm than that of bare CdS nanorods. Inorganic passivation by ZnS gives rise to the intensity increase and the lifetime decrease, while alloy formation with ZnS mainly brings about the blue shift.

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Hollow CdS nanoboxes, having paper-thin walls of well-defined facets, were synthesized at 170 degrees C via a simple reaction using Na(2)SeO(3) for interior quasitemplates and ethylenediamine for exterior molecular templates.

Zn x Cd1−x S (0 ≤ x ≤ 1) alloy nanoparticles have been fabricated facilely using ethylenediamine as a solvent-coordinating molecular template in water. Zn x Cd1−x S (x = 0.5) alloy nanoparticles of single-crystalline wurtzite structures having no staking faults have been constructed homogeneously to show that they are intermediate between ZnS and CdS in d-spacing and 2θ values. The photoluminescence of Zn x Cd1−x S alloy nanoparticles shifts largely to the blue with the composition increase of Zn to have the shortest wavelength at x = 0.9 (λmax = 480 nm for CdS, 396 nm for Zn0.9Cd0.1S, 424 nm for ZnS). The thermal treatment of as-prepared Zn x Cd1−x S alloy nanoparticles at 120 °C for 10 h has been found to increase photoluminescence intensity and lifetime by a factor of 5. This increase has been attributed to the decomposition of coordinated water molecules during annealing processes.

Both spectra of transient absorption (lambda(max) = 390 nm) and luminescence (lambda(max) = 590 nm) for the (4)T(1) state of Mn(2+) in ZnS nanoparticles shift to long wavelengths by 40 nm and broaden by 1.7 times as the state becomes banded. The (4)T(1) band of capping Mn(2+) in ZnS nanoparticles decays on the time scale of 0.35 mus, which is much shorter than either the decay time of the (4)T(1) state (2000 micros) for lattice-bound isolated Mn(2+) or that (180 micros) for surface-bound isolated Mn(2+) in ZnS nanoparticles.