NUV light-induced visible green emissions of Erbium-doped hierarchical Bi2Zr2O7 structures

We reported a facile strategy to synthesis of Er3+ doped Bi2Zr2O7 nanophosphors via hydrothermal route using Aloe Vera gel as a bio - surfactant. The photoluminescence spectra exhibit intense peaks centered at similar to 524, 547 and 660 nm, which were attributed to H-2(11/2) -> I-4(15/2), S-4(3/2)-> I-4(15/2) and F-4(9/2) -> I-4(15/2) transitions of Er3+ ions, respectively. The highest photoluminescence intensity was achieved in 5 mol % of Er3+ ions. The electric dipole-quadrupole (d-q) interaction was responsible for the concentration quenching. The fluorescence intensity ratio technique was utilized for optical thermometric properties of the nanophosphors in the temperature range of 303-463 K. At lower temperature (282 K) the relative sensor sensitivity of the optimized nanophosphor was found to be similar to 0.0621 K-1. Thermoluminescence glow curves of 5 mol % Er3+ ions doped nanophosphor irradiated with gamma-rays showed two peaks at similar to 120 and 203 degrees C. A thermoluminescence glow peak at similar to 120 degrees C showed good linearity with dose, simple glow curve structure, minimal fading and good reproducibility. The above results clearly showed that the optimized nanophosphor is quite useful in WLED's, TL dosimetry and optical thermometry applications.