Synthesis of NaYF4:Eu3+/Tb3+ nanostructures with diverse morphologies and their size- and morphology-dependent photoluminescence

Cubic α- and hexagonal β-phase lanthanide luminescent NaYF4:Eu3+/Tb3+ nanostructures with diverse morphologies were successfully synthesized via a mild solvothermal method. The effects of the synthetic parameters on the crystal phase structure, size and morphology of NaYF4:Eu3+/Tb3+ nanostructures were systematically investigated. By modifying the synthetic parameters, the crystal phase structure, size and morphology were well controlled, and the phase transition from cubic α- to hexagonal β- can be easily realized. Furthermore, the morphology evolution is revealed, and the surfactant modulating formation mechanisms with diverse morphologies was proposed. The photoluminescence properties were found to be in close correlation with their composition, phase structure and morphology. NaYF4:Eu3+/Tb3+ nanostructures possessing unique morphologies and highly efficient luminescence may find potential applications in optoelectronics, sensors and biolabels.