Related Experiment Video
Updated: Sep 23, 2025
07:03
Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
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Unveiling the role of the hexagonal polymorph on SrAl2O4-based phosphors
Rocío Estefanía Rojas-Hernandez1,2, Fernando Rubio-Marcos1, Aida Serrano3,4
1Electroceramic Department, Instituto de Cerámica y Vidrio, CSIC Kelsen 5 28049 Madrid Spain rociorojas@icv.csic.es.
RSC Advances
|May 13, 2022
Summary
Stabilizing the hexagonal strontium aluminate (SrAl2O4) polymorph is key for enhanced persistent luminescence. This hexagonal phase, when coexisting with the monoclinic form, preserves nanometric properties crucial for light-emitting materials.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Luminescence
Background:
- Strontium aluminate (SrAl2O4) is a key persistent luminescence material, known for chemical stability and long afterglow.
- Research often focuses on SrAl2O4 doped with europium and dysprosium.
- SrAl2O4 exists in monoclinic and hexagonal polymorphs, frequently coexisting, with unclear effects on luminescence.
Purpose of the Study:
- To systematically evaluate the impact of stabilizing the hexagonal SrAl2O4 polymorph.
- To clarify the role of hexagonal polymorph stabilization in polymorphic coexistence.
- To understand the relationship between hexagonal phase and luminescence properties.
Main Methods:
- Systematic evaluation of hexagonal SrAl2O4 polymorph stabilization.
- Analysis of monoclinic-hexagonal polymorphic coexistence.
- Investigation of nanometric properties preservation in SrAl2O4 systems.
Main Results:
- An interrelationship between the hexagonal polymorph and phosphorescence is crucial for luminescence.
- Stabilization of the hexagonal polymorph in coexistence is linked to preserving nanometric characteristics.
- The study clarifies the role of the hexagonal phase in SrAl2O4 luminescence.
Conclusions:
- The hexagonal SrAl2O4 polymorph plays a vital role in the luminescence of coexisting phases.
- Preserving nanometric structure is essential for achieving good luminescence properties.
- Findings facilitate the development of novel luminescent nanometric particles.
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