Control of electron transfer between Ce3+ and Cr3+ in the Y3Al5−xGaxO12 host via conduction band engineering
Control of electron transfer between Ce3+ and Cr3+ in the Y3Al5−xGaxO12 host via conduction band engineering
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DOI：
10.1039/c5tc00546a
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发表时间：
2015-05
影响因子：
6.4
通讯作者：
J. Ueda;P. Dorenbos;A. Bos;Keisuke Kuroishi;S. Tanabe
中科院分区：
文献类型：
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作者：
J. Ueda;P. Dorenbos;A. Bos;Keisuke Kuroishi;S. Tanabe
在稀土或过渡金属离子掺杂的无机长余辉发光材料中，掺杂阳离子中的定域电子向导带的转移过程是至关重要的。在Y3Al5−：Ce~(3+)-Cr~(3+)中，我们发现Ce~(3+)离子在紫外光和蓝光激发下光致电离产生的电子通过CB转移到Cr3+离子。在不同Ga含量的Yagg基质中，被Cr3+捕获的电子在400K到150K的不同温度下被热释放，这是因为我们通过增加Ga含量来减小CB和电子陷阱之间的能隙。通过构建包含Ce3+、Cr2+、价带(VB)和导带(CB)能级的真空参考结合能(VRBE)图，解释了不同Ga/Al比Yagg基质中的持续发光机制。
Among inorganic compounds doped with lanthanide or transition metal ions for persistent phosphors, the transfer process of the localized electron in the dopant cations to the conduction band (CB) is crucial. In Y3Al5−XGaxO12:Ce3+–Cr3+, we found that the electron produced by photoionization of the Ce3+ ion by UV and blue excitation transfers to the Cr3+ ion through the CB. The electron trapped by Cr3+ is thermally released at different temperatures from 400 K to 150 K in the YAGG host with different Ga content because we managed to decrease the energy gap between the CB and the electron trap by increasing the Ga content. The persistent luminescence mechanism has been explained by constructing the vacuum referred binding energy (VRBE) diagram comprising the Ce3+, Cr2+, valence band (VB) and conduction band (CB) level energies in the YAGG host with different Ga/Al ratios.