| Autor: |
Kohara, Yuto, Okada, Go, Tsuyumoto, Isao, Nanto, Hidehito |
| Zdroj: |
Journal of Materials Science: Materials in Electronics; Feb2023, Vol. 34 Issue 5, p1-9, 9p |
| Abstrakt: |
Radio-photoluminescence (RPL) properties of Eu-doped SrAl2O4 are studied focusing on the generation of a luminescent center by ionizing radiation of X-ray and its extinction by a thermally assisted charge transfer. The single phases of SrAl2O4 doped with Eu at concentrations of 0.05–1.0% are synthesized via solid-state reactions, as confirmed by X-ray diffractions analyses. They show photoluminescence (PL) due to both Eu3+ and Eu2+, and the PL intensity due to Eu3+ decreases after X-ray irradiation while the one due to Eu2+ notably increases. This indicates that Eu2+ as a luminescence center is generated as RPL through reduction from Eu3+ to Eu2+ by ionizing radiation of X-ray. Particularly, the 0.1% Eu-doped sample shows the highest sensitivity to X-ray dose, and the lowest detection limit is estimated to be 0.3 Gy with the present reader system. The RPL signal is reasonably stable, and it depends on the concentration of Eu. In the case of 1.0% Eu-doped sample, signal fading is not observed even after 20 times of PL measurement. Despite the stable signal, the RPL can be intentionally reversed by heat. Particularly, the 0.1% Eu-doped sample shows a 90% decrease by heating at 500 °C for 10 min. The erasure of signal was explained as a thermally assisted charge transfer, which is supported by the thermally stimulated luminescence studies. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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