Structural properties and near infrared photoluminescence of Nd3+ doped YBO3 nanocrystals

Structural and optical properties of YBO3 nanocrystals doped with trivalent neodymium ions (Nd3+), synthesized by the polymeric precursor method for the first time, were characterized for Nd3+ concentrations from 0.1 to 4.0 mol %. X-ray diffraction, high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), diffuse reflectance spectroscopy (DRS) and photoluminescence techniques were applied for characterization of the samples. The YBO3 nanocrystals presented high reflectance of similar to 85%, from ultraviolet to near-infrared and an optical bandgap of similar to 4.0 eV, being a good matrix for lanthanide ions because the yttrium ions (Y3+) can be replaced by Nd3+ without distortion of the crystalline structure. The nanocrystals doped with Nd3+ presented high crystallinity and average size of approximate to 303 nm. The DRS spectra showed ten Nd3+ absorption bands between 320 and 900 nm and the photoluminescence spectra, under excitation at 808 nm, showed that the YBO3 nanocrystals with 0.7 mol % of Nd3+ present the highest emission intensity from 1051 nm to 1069 nm. The measured lifetime of the Nd3+ energy level F-4(3/2) changed from 177 mu s to 63.8 mu s, while increasing the Nd3+ concentration from 0.1 mol % to 0.7 mol %, respectively. Photoluminescence quantum efficiencies of 0.98 and 0.80 were determined for the samples with 0.1 mol % and 0.7 mol % of Nd3+, respectively.