Tien Ching-Ho, Fang Jen-Yu, Chen Lung-Chien
Department of Electrical Engineering, Tunghai University, Taichung City, 407224, Taiwan.
Department of Electro-Optical Engineering, National Taipei University of Technology, Taipei, 10608, Taiwan.
Sci Rep. 2025 Jan 7;15(1):1215. doi: 10.1038/s41598-025-85713-9.
This work reports on the preparation process of a double-layer perovskite active layer. The first active layer film, CsKPEAPbIBr, was fabricated using a spin-coating method, while the second active layer, MAPbBr, was deposited using MAPbBr single crystals as the evaporation source. Additionally, doping the PEDOT: PSS hole transport layer with ETA and EDA can enhance the uniformity of the perovskite film and reduce voids, improving charge transport efficiency. It proposed the use of an MABr layer to passivate the device interface structure, enhancing the injection and recombination efficiency of charge carriers. In the study of the single-layer CsKPEAPbIBr perovskite, the optimized brightness reached 513.4 cd/m², with an external quantum efficiency (EQE) of 0.24% after doping and modification. When the second active layer MAPbBr was introduced, the results showed that as the voltage increased from 4 V to 10 V, the LED emission color changed from orange-red to green. This change was attributed to the variation in the recombination positions of charge carriers in different bandgap materials at different voltages. At low voltage, carriers recombine in the layer with a smaller bandgap, emitting red light; whereas at high voltage, carriers recombine in the layer with a larger bandgap, emitting green light.
这项工作报道了双层钙钛矿活性层的制备过程。第一个活性层薄膜CsKPEAPbIBr采用旋涂法制备，而第二个活性层MAPbBr则以MAPbBr单晶作为蒸发源进行沉积。此外，用ETA和EDA对PEDOT:PSS空穴传输层进行掺杂可以提高钙钛矿薄膜的均匀性并减少空隙，从而提高电荷传输效率。研究提出使用MABr层来钝化器件界面结构，提高电荷载流子的注入和复合效率。在单层CsKPEAPbIBr钙钛矿的研究中，优化后的亮度达到513.4 cd/m²，掺杂和改性后的外量子效率（EQE）为0.24%。当引入第二个活性层MAPbBr时，结果表明，随着电压从4 V增加到10 V，LED发射颜色从橙红色变为绿色。这种变化归因于不同带隙材料中电荷载流子在不同电压下复合位置的变化。在低电压下，载流子在带隙较小的层中复合，发出红光；而在高电压下，载流子在带隙较大的层中复合，发出绿光。
