在化佩洛夫斯基特纳米晶体中依赖热载体冷却
Junsheng Chen1,2, Maria E Messing3, Kaibo Zheng1,4
1Chemical Physics and NanoLund , Lund University , Box 124, 22100 Lund , Sweden.
Journal of the American Chemical Society
|January 29, 2019
概括
化 (LHP) 中的热载体冷却取决于激发能量和阴离子类型. 有机 (MA+,FA+) 与框架的相互作用比Cs+更强,影响LHP纳米晶体的冷却速率.
科学领域:
- 材料科学
- 光物理学
- 纳米技术
背景情况:
- 化 Perowskites (LHPs) 纳米晶体 (NCs) 具有显著的光物理特性,使其适用于太阳能电池,照明和显示器.
- 热载体冷却 (HC) 是一个关键的光物理过程,影响了基于LHPNC的设备的性能.
- 化学工程,特别是阳离子交换,可以优化LHP的特性.
研究的目的:
- 为了研究不同 (,甲基,) 的LHPNC中的热载体 (HC) 放松动力学.
- 了解激发强度和能量对LHPNC的冷却的影响.
- 阐明阴离子类型在HC冷却过程中的作用.
主要方法:
- 使用秒瞬时吸收光谱来研究HC放松动态.
- 由CsPbBr3,MAPbBr3和FAPbBr3组成的经过检查的LHPNC.
- 在不同激发能量和低激发强度下研究了HC冷却.
主要成果:
- 液压冷却取决于激发强度和能量.
- 更高的激发能导致更长的HC放松时间.
- 在350nm激发时,冷却时间按照以下顺序进行:CsPbBr3 > MAPbBr3 > FAPbBr3.
结论:
- 阴离子类型对LHPNC中的HC放松动态有显著影响.
- 与Cs+相比,有机离子 (MA+,FA+) 和Pb-Br框架之间的更强相互作用解释了观察到的离子依赖.
- 对于设计高性能LHP设备来说,了解阴离子依赖的HC冷却至关重要.
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