View in EDS

Simultaneous oxidation of Mn2+ to Mn4+ by devitrification of transparent glassy Na2Ge4O9: Mn.

Saved in:
Bibliographic Details
Title: Simultaneous oxidation of Mn2+ to Mn4+ by devitrification of transparent glassy Na2Ge4O9: Mn.
Authors: Madkhli, Aysh Y.1 (AUTHOR) amadkhli@jazanu.edu.sa
Source: Ceramics International. Jul2024, Vol. 50 Issue 14, p24913-24920. 8p.
Subjects: Devitrification, Electron paramagnetic resonance spectroscopy, Chemical formulas, Optical spectroscopy, Oxidation states, Valence fluctuations
Abstract: To generate red emissions, manganese (IV) ions have recently gained recognition as potent non-rare-earth activators. However, the oxide and fluoride hosts that offer suitable environments for Mn4+ require careful preparation, involving precise control of reaction parameters like redox equilibrium and temperature. In the current work, we show simultaneous oxidation of Mn2+ to Mn4+ by devitrification of glassy Na 2 Ge 4 O 9 : Mn under moderate atmospheric conditions and under the argon atmosphere. The G-sample was devitrified via thermal treatment after the parent glass, which shares the same chemical formula as dilithium tetragermanate (Na 2 Ge 4 O 9), was created through the use of traditional melt-quenching (MQ). Optical spectroscopy and electron paramagnetic resonance (EPR) spectroscopic are utilized to confirm the Mn2+ oxidation to Mn4+ from glass stat to glass ceramic after thermal treatment. Due to the transition from Mn2+ to Mn4+, a sharp 668 nm emission peak is recorded whereas the red emission peaking at 611 nm monitored in glass is steadily reduced. The temperature-dependent PL spectra of the Na 2 Ge 4 O 9 :0.1Mn+4, red-emitting GC in the temperature range ∼295–490 K were recorded. The PL emission intensity decreases gradually with increasing the temperature. The technique showcased for producing Na 2 Ge 4 O 9 :Mn4+ phosphors could be expanded to synthesize other phosphors incorporating activators possessing a high oxidation state. [ABSTRACT FROM AUTHOR]
Copyright of Ceramics International is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:To generate red emissions, manganese (IV) ions have recently gained recognition as potent non-rare-earth activators. However, the oxide and fluoride hosts that offer suitable environments for Mn4+ require careful preparation, involving precise control of reaction parameters like redox equilibrium and temperature. In the current work, we show simultaneous oxidation of Mn2+ to Mn4+ by devitrification of glassy Na 2 Ge 4 O 9 : Mn under moderate atmospheric conditions and under the argon atmosphere. The G-sample was devitrified via thermal treatment after the parent glass, which shares the same chemical formula as dilithium tetragermanate (Na 2 Ge 4 O 9), was created through the use of traditional melt-quenching (MQ). Optical spectroscopy and electron paramagnetic resonance (EPR) spectroscopic are utilized to confirm the Mn2+ oxidation to Mn4+ from glass stat to glass ceramic after thermal treatment. Due to the transition from Mn2+ to Mn4+, a sharp 668 nm emission peak is recorded whereas the red emission peaking at 611 nm monitored in glass is steadily reduced. The temperature-dependent PL spectra of the Na 2 Ge 4 O 9 :0.1Mn+4, red-emitting GC in the temperature range ∼295–490 K were recorded. The PL emission intensity decreases gradually with increasing the temperature. The technique showcased for producing Na 2 Ge 4 O 9 :Mn4+ phosphors could be expanded to synthesize other phosphors incorporating activators possessing a high oxidation state. [ABSTRACT FROM AUTHOR]
ISSN:02728842
DOI:10.1016/j.ceramint.2023.12.170