Low Temperature Synthesis and Photoluminescence Properties of Tb Doped YAlO3 Nanoparticles

We have synthesized Tb doped YAlO3 nanoparticles through combustion synthesis utilizing mixture of equimolar citric-ammonium nitrate as the fuel at temperatures as low as 400 °C. Phase purity of the synthesized materials is confirmed through powder x-ray diffraction. Interestingly, Tb doped samples crystallize in the orthogonal system at as low as 400 °C, the lattice parameter increases owing to the increase in the ionic radii of the doped Tb atoms as compared to the parent Y atoms. The optical band gap of the doped sample reduces from 4.31 eV for undoped to 4.10 eV in case of 5% Tb doped bulk sample. Further we observe significantly lowering in bandgap to 3.75 eV in case of the same nanoparticles. We demonstrate that 2.5% and 5% Tb doped samples exhibit excellent photoluminescence properties and can be tuned to emit white light under appropriate excitation.