Molten salt synthesis and luminescent properties of YVO4:Eu nanocrystalline phosphors

YVO 4 :Eu nanocrystalline phosphors were successfully prepared at 400 °C in equal moles of NaNO 3 and KNO 3 molten salts. NaOH concentration and annealing temperature played important roles in phase purity and crystallinity of the nanocrystallines, and the optimum NaOH concentration and annealing temperature were 6:40 and 400 °C, respectively. The nanocrystallines were well crystallized with a cubic morphology in an average grain size of 18 nm. Upon excitation of the vanadate groups at 314 nm, YVO 4 :Eu nanocrystallines exhibited the characteristic emission of Eu 3+ , which indicated that there was an energy transfer from vanadate groups to Eu 3+ . Moreover, the influence of superficial effect, especially the dangling bonds on the structure and luminescent properties of the nanocrystallines was discussed in detail.