Optical tuning in lanthanide-based nanostructures

Luminescent materials comprising lanthanide dopants are characterized with unique optical properties such as large Stokes shift, long excited state lifetime, and high resistance to photon bleaching and optical blinking. Particularly, the complex energy levels in lanthanide ions are able to convert low-energy near infrared photons into higher-energy visible and ultraviolet emissions. In recent years, nanostructured host materials are increasingly used to construct novel lanthanide luminescent materials. By incorporating otherwise incompatible lanthanide ions into separate layers of a core–shell nanostructure, the interactions of dopant ions can be precisely controlled for realizing unprecedented luminescence processes. Nanostructural engineering also allows integration and coupling with quantum dots/dye molecules and plasmon structures for synergistic optical modulation. In this review, we summarize various strategies for tuning lanthanide luminescence based on the use of nanostructured materials. Typical example applications enabled by these advanced luminescent nanomaterials will also be discussed.