This work explores the sensitization of luminescent lanthanide Tb 3+ and Eu 3+ cations by the electronic structure of zinc sulfide (ZnS) semiconductor nanoparticles. Excitation spectra collected, while monitoring the lanthanide emission bands, reveals that the ZnS nanoparticles act as an antenna for the sensitization of Tb 3+ and Eu 3+ . The mechanism of lanthanide ion luminescence sensitization is rationalized in terms of an energy and charge transfer between trap sites and is based on a semi-empirical model, proposed by Dorenbos and coworkers, 1 -6 to describe the energy level scheme. This model implies that the mechanisms of luminescence sensitization of Tb 3+ and Eu 3+ in ZnS nanoparticles are different; namely Tb 3+ acts as a hole trap, while Eu 3+ acts as an electron trap. Further testing of this model is made by extending the studies from ZnS nanoparticles to other II-VI semiconductor materials; namely, CdSe, CdS, and ZnSe.

The electronic structure of CdSe semiconductor nanocrystals has been used to sensitize Tb3+ in solution by incorporation of Tb3+ cations into the nanocrystals during synthesis. Doping of luminescent Tb3+ metal ions in semiconductor nanocrystals utilizes the positive attributes of both species' photophysical properties, resulting in a final product with long luminescence lifetimes, sharp emission bands, high absorptivities, and strong resistance to decomposition. This strategy also helps protect the lanthanide cations from nonradiative deactivation from C-H, N-H, and O-H oscillators of solvent molecules or traditional organic lanthanide ligands, leading to long Tb3+ luminescence lifetimes. This new type of nanomaterial synergistically combines the photophysical properties of nanocrystals and Tb3+.

Nitrogen‐containing carbon nanotube cups are crosslinked with glutaraldehyde to form capsule‐shaped nanostructures. Introduction of commercially available gold nanoparticles prior to the crosslinkage process results in their encapsulation within the interior cavity of the linked structures (see image). A similar encapsulation of ZnS:Tb nanoparticles shows the general applicability of the system. Such a facile protocol alludes to drug‐delivery and energy‐storage applications.

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