Synthesis and characterization of HA/YVO4: Yb3+, Er3+ up-conversion luminescent nano-rods

In this paper, hydroxyapatite (HA) nano-rods have been successfully functionalized by depositing YVO4: Yb3+, Er3+ up-converting nanoparticles on the surfaces via a facile sol–gel technique. X-ray diffraction, field emission scanning electron microscopy, energy disperse X-ray spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and photoluminescence spectra were used to characterize the structure, morphology and up-conversion luminescent properties of the samples. The results indicate that the HA nano-rods have been successfully coated by YVO4: Yb3+, Er3+ up-converting nanoparticles, and the samples exhibit bright green up-conversion luminescence upon the excitation of a 980 nm diode laser. Furthermore, the optical intensity of the composites can be controlled by varying the depositing cycles of YVO4: Yb3+, Er3+ up-converting nanoparticles. This up-conversion luminescent HA may find important applications in the fields of in vivo bio-imaging and a drug delivery system.