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在稀土合硫化材料上探测结构缺陷和X射线诱导的持久发光机制

Karina T Fonseca¹, Danilo O A Santos¹, Fernando A Garcia²

¹Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo-SP, 05508-000, Brazil. lucascvr@iq.usp.br.

Dalton transactions (Cambridge, England : 2003)

|March 18, 2025

概括

硫化物 (SrS) 的持续发光与晶体缺陷有关. 配合稀土离子对SRS的配合增强了持续发光衰变时间,为先进的成像和传感应用提供了潜力.

科学领域:

材料科学材料科学材料科学
固态物理固态物理
发光的光度是非常的低.

背景情况:

持久发光源源于晶体结构中的点缺陷,通常由多离子引入.
硫化 (SrS) 是X射线激活的高效宿主材料,由于其发光率和X射线吸收.
之前的研究集中在紫外线/可见光发光;这项研究调查了稀土杂的SRS中X射线诱导的机制.

研究的目的:

为了阐明稀土合的SRS光体中的X射线诱导发光机制.
调查晶体缺陷和剂离子在持续发光中的作用.
探索基于SRS的材料在X射线成像和传感方面的潜力.

主要方法:

同步射线辐射技术,包括扩展X射线吸收细结构 (EXAFS) 和X射线吸收近边缘结构 (XANES).
进行X射线激发光学发光 (XEOL) 测量.
在单一和联合合的SRS样本中分析持久发光衰变时间.

主要成果:

EXAFS表示,稀土离子主要占据SRS晶格中的替代位点,导致基于离子半径的扭曲.
XANES揭示了SRS:Ce和SRS:Eu,Ce中的Ce的混合价值状态,并确定了X射线照射下的电荷转移过程.
与联合剂的SRS样本相比,与单一剂的样本相比,持续发光衰变时间显著更长,这归因于缺陷度增加.

结论:

稀土兴奋剂和X射线辐射诱导SRS光体中的复杂缺陷结构和电荷转移动态.
辅助兴奋剂策略可以通过增加缺陷密度来有效地增强持久发光特性.
这些发现对于开发用于医学成像,数据存储和传感器应用的先进X射线光器至关重要.

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