|
NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR) >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Engineering and Materials Sciences (IJEMS) >
IJEMS Vol.19 [2012] >
IJEMS Vol.19(3) [June 2012] >
| Title: | Effect of crystallite size on electron spin resonance of Gd3+ and luminescence of Eu3+ doped in La6WO12 |
| Authors: | Devi, V Rama
Kumar, B Vijaya
Velchuri, Radha
Suresh, Palla
Ravi, G
Vithal, M |
| Keywords: | Sol-gel
Powder XRD
Crystallite size
Luminescence
ESR |
| Issue Date: | Jun-2012 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | Nano-sized Eu3+ and Gd3+ doped lanthanum
tungstates of composition La6-xLnxWO12 (Ln =
Eu, Gd; 0 ≤ x ≤ 0.2) are prepared by sol-gel complexation method. These samples
are characterized by powder X-ray diffraction (XRD).
The average crystallite size is calculated from the XRD using Scherer’s
equation. The electron spin resonance (ESR) spectrum of Gd3+ doped
lanthanum tungstate (La6WO12) gives characteristic “U”
type spectrum. The luminescence spectrum of Eu3+ doped La6WO12
gives characteristic 5D0→7Fn (n = 0 to 4) bands due to trivalent
europium ions.
The intensity of 5D0→7F2 transition
decreases with increase in the sintering temperature due to depletion of
surface Eu3+ ions. The intensity of 5D0→7F2
sintered at 700°C has highest intensity and may have laser applications. |
| Page(s): | 204-208 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-1017 (Online); 0971-4588 (Print) |
| Source: | IJEMS Vol.19(3) [June 2012]
|
|
