在MAPbBr3晶体中的离子场选揭示了X射线检测中的残留灵敏度
Agustin O Alvarez1, Ferdinand Lédée2, Marisé García-Batlle1
1Institute of Advanced Materials, Universitat Jaume I, 12071 Castelló, Spain.
ACS physical chemistry Au
|July 31, 2023
概括
金属化物矿对X射线检测有希望,但不稳定性是一个问题. 这项研究揭示了离子迁移如何影响设备性能,并提出了一种量化离子特性以提高稳定性的方法.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 探测器物理学的物理
背景情况:
- 金属化物矿为高灵敏度的X射线检测提供最佳的光电子特性.
- 设备性能受到接触退化和电流不稳定性所限制,这与双电子离子导电性有关.
- 甲基鉛化物 (MAPbBr3) 是这些应用的关键材料.
研究的目的:
- 为了描述在X射线发射下MAPBBr探测器的长期黑暗电流和光电流.
- 为了研究离子导电性对设备稳定性和性能的影响.
- 开发一种用于估计矿X射线探测器中的离子移动性和度的方法.
主要方法:
- 毫米厚的MAPBBr3单个和多晶样品的实验性表征.
- 在X射线照射下测量暗电流和光电流在偏差后短路时.
- 漂移扩散数值模拟以模拟电荷动力学和离子场效应.
主要成果:
- 暗电流和探测器灵敏度在应用偏差后短路时表现出类似的趋势.
- 与离子相关的内置场显著影响电荷动力学,导致长时间的放松时间 (长达几十小时).
- 离子场继续影响电荷动力学,即使在低光生成速率下也是如此.
结论:
- 矿的双电子离子导电性导致由于离子迁移而导致性能限制.
- 了解和减轻离子场的影响对于稳定和敏感的X射线探测器至关重要.
- 提出了一种用于估计离子流动性和度的新方法,有助于材料优化.
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