Silica coated, water dispersible and photoluminescent Y (V, P)O_4:Eu~(3+),Bi~(3+) nanophosphors

摘要

We propose an approach for silica encapsulation of YV_(0.7)P_(0.3)O_4:Eu~(3+), Bi~(3+) nanophosphors through a microemulsion process. The resulting YV_(0.7)P(0.3)O_4:Eu~(3+), Bi~(3+)@SiO_2 core-shell nanophosphors were characterized by transmission electron microscopy, UV vis absorption and photoluminescence spectroscopy, energy-dispersive x-ray analysis (EDAX), selected area electron diffraction and zeta-potential measurements. The obtained nanocomposites have quite a uniform spherical shape and diameters of about 15 nm. Zeta-potential measurements show that coated particles are stable at high volume fractions and can endure large variations in pH and electrolyte concentration without coalescence. These core-shell nanophosphors could also be used as ultrasensitive biological labels, because they are obtained in nanoscale and well dispersible in water.