压力诱导的相变,可逆无形化和异常可见光响应在有机烯矿中
Yonggang Wang1,2,3, Xujie Lü1, Wenge Yang2,4
1High Pressure Science and Engineering Center, University of Nevada , Las Vegas, Nevada 89154, United States.
Journal of the American Chemical Society
|August 19, 2015
概括
在有机胺矿 (MAPbBr3) 中,水静压会诱导相变和可逆无形化. 这种压力调整保持了半导体特性和可见光响应,为光伏设备提供了潜力.
科学领域:
- 材料科学
- 凝聚物质物理学
- 固态化学
背景情况:
- 液压压力是调整材料性能的一个关键技术,它可以替代化学压力.
- 有机胺矿,如CH3NH3PbBr3 (MAPbBr3),是新型应用的有希望的材料.
- 了解压力诱导的相稳定性和电子性质对于材料设计至关重要.
研究的目的:
- 在高达34GPa的水静压下研究MAPbBr3的相稳定性.
- 检查MAPbBr3的可见光反应作为压力的函数.
- 探索压力调节的MAPbBr3在光伏设备中的潜在应用.
主要方法:
- 在现场光发,电阻和光电流测量.
- 在室温下施加高达34GPa的静水压力.
- 理论分析的第一原则模拟.
主要成果:
- 观察到2GPa以下的两个相变化 (Pm3̅m到Im3̅,然后到Pnma) 和从2GPa左右开始的可逆无形化.
- 由于相互竞争的压缩和无形化效应,带间隙演变异常 (红移,然后蓝移).
- 显著增加阻力 (大小5级) 25 GPa,保留半导体特性和光响应.
结论:
- 液压可以有效调整MAPbBr3的晶体结构和电子特性.
- 在MAPbBr3中,压力诱导的无形化导致阻力发生显著变化,同时保持光吸收能力.
- 在水立压下,MAPbBr3显示出光伏设备作为开关器或控制器以及无形有机金属复合材料作为吸光器的应用潜力.
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