在与混合化物系统中依赖组合的波段结构参数和波段间隙曲效应:循环电压测量调查
Suyog Sanjay Mane1, Archisman Sinha1, Santosh Krishna Haram1
1Department of Chemistry, Savitribai Phule Pune University, Ganeshkhind Rd, Ganeshkhind, Pune, Maharashtra 411007, India. santosh.haram@unipune.ac.in.
Physical chemistry chemical physics : PCCP
|August 14, 2024
概括
化物替代在化物化物化物化物矿纳米晶体 (PNCs) 调节频段边缘参数和频段间隙. 尺寸量化会在这些量子点中产生负带间隙弓形效应.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 太阳能光伏发电是如何实现的
背景情况:
- 化物矿矿纳米晶体 (PNCs) 是光电子应用的有希望的材料.
- 调整它们的电子特性对于设备优化至关重要.
研究的目的:
- 研究化物替代 (I, Br, Cl) 对 CsPbX3 PNC 带边参数和带间隙曲的影响.
- 为了将这些特性与纳米晶体大小和组成相关联.
主要方法:
- 用于合成具有不同化物组成的CsPbX3 PNCs的热注入方法.
- 粉末X射线衍射 (XRD) 和高分辨率传输电子显微镜 (HR-TEM) 用于结构和尺寸分析.
- 循环电压测量 (CV) 用于确定波段边缘位置 (导电和价值波段).
- 光发光 (PL) 光谱法用于评估量子点的形成和尺寸分布.
主要成果:
- 合成了高度结晶的,立方体的CsPbX3 PNC (7-20 nm) 具有狭窄的尺寸分布.
- 光学带间隙系统地转移到更短的波长,随着Br和Cl含量的增加.
- 循环电压测量显示,从I到Cl替换时,价值带边缘 (h1) 显著下降,导电带边缘 (e1) 略微增加.
- 观察到负带间隙曲,并归因于量子束效应.
结论:
- 化物组成显著影响CsPbX3 PNCs的电子带结构.
- 确定带边界参数对于设计具有适当电荷传输层的高效异质连接至关重要.
- 尺寸量化在观察到的带隙曲中起着关键作用,为带隙工程提供了一条途径.
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