Optical Properties of Rare-Earth Doped YBO3 Phosphor Materials

YBO3:Eu3+, a red phosphor, is of current interest due to its application in plasma display panels (PDPs) and white light emitting diodes (WLEDs). YBO3:Eu3+ offers exceptional properties such as high optical damage threshold, high quantum efficiency in deep ultraviolet region (UV) but this material has a chromaticity problem due to its orange (591 nm, O) and red (611 & 627 nm, R) emission. The red color along with high efficiency is desirable for PDPs and phosphor-based WLEDs applications. In this work to address chromaticity problem and efficiency in the near UV region, we have investigated the optical and vibrational properties of hydro(solvo)thermal synthesized YBO3:Eu3+ and YBO3: Eu3+ tri-doped Ce3+,Tb3+ materials by X-ray diffraction, scanning electron microscope-cathodoluminescence, photoluminescence, photoluminescence excitation, and Raman spectroscopy techniques. The different microstructures of YBO3:Eu3+ have synthesized with hydro(solvo)thermal technique using different molar ratios of starting precursors and solvents. The high chromaticity is achieved with honey-comb morphology of Y:B 1:2 and ethanol solvent. Raman spectroscopy has been used to correlate the high chromaticity to structural disorder in YBO3:Eu3+ structure. Further, hydro(solvo)thermally synthesized YBO3: Eu3+ tri-doped Ce3+,Tb3+ samples have shown a promise way to obtain the high R/O ratio along with efficient near UV excitation states. Raman vibrational bands show a systematic change, with Tb3+ concentration, in the B3O9 ring terminal oxygen bending mode related to the host lattice site corresponding to yttrium where the dopant ions substite. The structural changes are interpreted as variations in the local neighborhood of these sites in the YBO3:Ce3+,Tb3+,Eu3+ crystal structure.

Name thesis:degree_name

Doctor of Philosophy

Grantor

Texas Tech University

Year dc:date.issued

2014

Author dc:creator

• Sohal, Sandeep

Advisor dc:contributor.advisor

• Holtz, Mark

Committee members dc:contributor.committeemember

• Bernussi, Aryton
• Chaudhuri, Jharna
• Peralta, Luis Grave de

Handle dc:identifier.uri

https://hdl.handle.net/2346/106699

OAI identifier oai:identifier

oai:ttu-ir.tdl.org:2346/106699