Intrinsic point defects in inorganic perovskite CsPbI3 from first-principles prediction
Intrinsic point defects in inorganic perovskite CsPbI3 from first-principles prediction
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第一性原理预测无机钙钛矿 CsPbI3 的本征点缺陷
DOI：
10.1063/1.5001535
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发表时间：
2017-10-16
影响因子：
4
通讯作者：
Huang, Wei
中科院分区：
文献类型：
--
作者：
Li, Yifan;Zhang, Chenhui;Huang, Wei
立方无机钙钛矿结构的CsPbI 3是一种直接带隙半导体，在太阳能电池、发光二极管和激光器等光电领域具有广阔的应用前景。半导体中的本征缺陷对载流子的电导率、载流子复合效率等起着至关重要的作用，但立方结构CsPbI 3的热力学稳定性和本征缺陷物理机制尚不清楚。通过第一性原理计算，我们研究了CsPbI_3晶体生长的热力学过程，发现CsPbI_3晶体生长的窗口很窄，Cs的浓度对CsPbI_3晶体的生长有重要影响。在富Pb条件下，VPb和VI可以将费米能钉扎在带隙的中间，这导致低载流子浓度。在贫Pb条件下，VPb是主要缺陷，并且材料具有高浓度的空穴载流子和长寿命。我们目前的工作提供了一个洞察力的立方CsPbI 3的缺陷物理，将有利于光电子器件的研究。
Cubic inorganic perovskite CsPbI3 is a direct bandgap semiconductor, which is promising for optoelectronic applications, such as solar cells, light emitting diodes, and lasers. The intrinsic defects in semiconductors play crucial roles in determining carrier conductivity, the efficiency of carrier recombination, and so on. However, the thermodynamic stability and intrinsic defect physics are still unclear for cubic CsPbI3. By using the first-principles calculations, we study the thermodynamic process and find out that the window for CsPbI3 growth is quite narrow and the concentration of Cs is important for cubic CsPbI3 growth. Under Pb-rich conditions, VPb and VI can pin the Fermi energy in the middle of the bandgap, which results in a low carrier concentration. Under Pb-poor conditions, VPb is the dominant defect and the material has a high concentration of hole carriers with a long lifetime. Our present work gives an insight view of the defect physics of cubic CsPbI3 and will be beneficial for optoelect...