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Low-energy Cathodoluminescence for OxyNitride Phosphors
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Pigments and Near-Infrared Phosphors Based on Mn5
Sanja Kuzman1, Tatjana Dramićanin1, Anatoli I Popov2
1Centre of Excellence for Photoconversion, Vinča Institute of Nuclear Sciences-National Institute of the Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia.
Nanomaterials (Basel, Switzerland)
|February 25, 2025
Summary
This study explores the optical properties of manganese ions in the 5+ valence state (Mn5+). We detail their role in pigments and phosphors, and their applications in luminescence thermometry.
Area of Science:
- Materials Science
- Solid State Chemistry
- Spectroscopy
Background:
- Manganese ions in the 5+ valence state (Mn5+) exhibit unique optical properties crucial for pigments and phosphors.
- Understanding Mn5+ ion behavior in crystalline matrices is key to developing advanced optical materials.
Purpose of the Study:
- To investigate the optical properties of Mn5+ ions in crystalline hosts.
- To elucidate the electronic transitions responsible for coloration in Mn5+-based pigments.
- To analyze the mechanisms behind near-infrared emission in Mn5+-activated phosphors and their applications.
Main Methods:
- Analysis of electronic configurations and crystal field theory for Mn5+ ions ([Ar]3d2).
- Spectroscopic examination of Mn5+-based pigments and phosphors.
- Correlation of optical properties with crystal field strength and nephelauxetic effect.
Main Results:
- The intense coloration of Mn5+ pigments arises from the spin-allowed 3A2 → 3T1(3F) absorption.
- Narrow-band near-infrared emission in Mn5+ phosphors originates from the spin-forbidden 1E → 3A2 transition.
- A linear relationship was demonstrated between 1E state energy and the nephelauxetic parameter β1 for Mn5+ phosphors.
Conclusions:
- Mn5+ ions can maintain their valence state in specific crystalline environments.
- Crystal field strength significantly influences pigment color, while the nephelauxetic effect governs phosphor emission.
- Mn5+ phosphors show promise for applications in luminescence thermometry.
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