Optical characterization of infrared emitting Nd³⁺ doped hydroxyapatite nanoparticles prepared by hydrothermal method

Trivalent Nd doped hydroxyapatite (HAp) nanoparticles were prepared by a hydrothermal method using calcium nitrate and diammonium phosphate as precursors. Well crystallized nanoparticles of size less than 200 nm with hexagonal plate and rod morphologies were obtained at a reaction temperature of 180 °C. Under 808 nm excitation the nanoparticles exhibit strong near infrared emission at 1064 nm. All the emission spectral properties such as emission intensity and fluorescence decay time are found to decrease with Nd³⁺ concentration. In Hap 0.5% Nd shows the highest decay time of 159 μs and highest emission at 1064 nm emission.