Up-conversion luminescence in Ho3+ and Tm3+ co-doped Y2O3:Yb3+ fine powders obtained through aerosol decomposition
Abstract
Fine yttrium oxide powders doped with Yb3+ and co-doped either with Tm3+ or Ho3+ were synthesized via spray pyrolysis at 900 °C using 0.1 M nitrate precursor. Synthesized powders were additionally thermally treated at 1100 °C for 24 h. The characterization was done through X-ray powder diffraction (XRPD), scanning electron microscopy (SEM) and photoluminescent measurements (PL). Generation of cubic bixbyte-structure with space group Ia-3 is confirmed in all samples. Spherical particles with the mean size of ∼400 nm, generated through volume precipitation of much smaller nanograins, expose certain degree of porosity which alters particle morphology during additional thermal treatment. Powders optical characterizations include measurement of up-conversion emission spectra after excitation at 978 nm, as well as determination of emission lifetimes and up-converted emission intensity dependence on excitation power. Dominant green (5F4, 5S2 → 5I8) and blue (1G4 → 3H6) emission is found for H...o3+ and Tm3+ samples, respectively. The amplified emission intensities and enhanced lifetime in thermally treated samples are correlated with the powders morphological and structural changes.
Keywords:
spray pyrolysis / up-convertors / Y2O3 / luminescence / Yb3+ / Ho3+Source:
Optical Materials, 2012, 35, 1, 38-44Publisher:
- Elsevier
Projects:
- Rational design and synthesis of biologically active and coordination compounds and functional materials, relevant for (bio)nanotechnology (RS-172035)
- Materials of Reduced Dimensions for Efficient Light Harvesting and Energy conversion (RS-45020)
DOI: 10.1016/j.optmat.2012.06.019
ISSN: 0925-3467