Synthesis and luminescence of Eu3+ doped hydroxyapatite nanocrystallines: Effects of calcinations and Eu3+ content

Eu3+ doped hydroxyapatite (Eu-HAP) luminescent nanocrystallines were prepared by ultrasound assisted precipitation method. Aiming to seek a compromise proposal for achieving high luminescence and nanocrystallines, the effects of calcinations temperature and Eu3+ doping content on luminescence property as well as phase composition, crystal size and crystallinity of Eu-HAP crystals were investigated. The results showed that the luminescence of Eu-HAP was enhanced by the thermal treatment and the increasing Eu doping content. However, the higher temperature and the excess Eu resulted in the size increase and phase composition change of HAP respectively. The 2% Eu doping content and calcinations temperature of 600 °C were preferred for preparing Eu-HAP nanocrystallines with strong luminescence. The Eu-HAP nanocrystallines were about 20–40 nm in diameter (TEM) and could be well dispersed in water to form aqueous suspension of about 140 nm (DLS intensity-averaged diameter). Eu-HAP nanocrystalline could be used as a fluorescent probe for cell labeling.