Tunable rapid microwave synthesis of up-converting hexagonal NaYxGdyYbzEr(1−x−y−z)F4 nanocrystals in large quantity

Various sizes of pure hexagonal nanocrystals of NaYxGdyYbzEr(1−x−y−z)F4 were prepared by simple synthesis using microwave radiation. Ionic liquid bmimCl was used as a solvent and NH4F as a fluorination agent. Nanocrystal sizes were controlled by varying water volume or by addition of various surfactants.