对可见光吸收的双矿的缺陷诱导带边重建
Adam H Slavney1, Linn Leppert2,3, Davide Bartesaghi4,5
1Department of Chemistry, Stanford University , Stanford, California 94305, United States.
Journal of the American Chemical Society
|March 30, 2017
概括
稀释合金显著减少化物双矿的带隙,使得太阳能电池性能得到改善. 这一突破使得这些毒性较低的材料与矿具有竞争力.
科学领域:
- 材料科学
- 太阳能发电
- 固态化学
背景情况:
- 化物双矿被认为是矿太阳能电池的毒性较低的替代品.
- 现有的化物双矿具有宽带间隙,限制了它们的可见光吸收能力.
- Cs2AgBiBr6 (1) 是一种代表性的化物双矿,带隙为1.95 eV.
研究的目的:
- 研究稀释合金对Cs2AgBiBr6带隙的影响.
- 通过测量载体寿命来评估合金化物双矿的光伏潜力.
- 为了探索化物双矿与基吸收剂的竞争.
主要方法:
- 用其他元素稀释Cs2AgBiBr6的合金.
- 带隙能量测量
- 时间解析的光导度测量以确定载体寿命.
主要成果:
- 稀释合金将Cs2AgBiBr6的带隙降低了大约0. 5 eV.
- 合金材料具有长寿命的电荷载体,寿命为微秒.
- 合金矿的带隙能量和载体寿命与以为基础的 (CH3NH3) PbI3相比较.
结论:
- 稀释合金是一种有效的策略,可以缩小化物双矿的带隙.
- 观察到的长载体寿命表明光伏应用的巨大潜力.
- 了解杂质轨道的作用为优化化物双矿的太阳能转化提供了一条路线.
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