When it comes to building high-efficiency thin-film optoelectronic devices, we are constantly striving to improve the efficiency of charge transport and injection. Device performance is hampered by the low mobility and injection ability of organic charge transporting materials that are routinely used. In this paper, we show that instead of using organics as a hole transporting layer, metal halide perovskite can be used to fabricate high-efficiency carbon dots-based light-emitting diodes for the first time. The organic light-emitting layer and the underlying perovskite layer combine to form an organic–inorganic perovskite planar heterojunction, and the sufficient contact at the junction takes advantage of the high charge mobility of perovskite, facilitating the hole transportation and injection. Moreover, the interaction between perovskite and the organic emitting layer can be engineered via manipulating the halogenic component, thickness, surface morphology, etc., contributing to the device optimization and the understanding of the carrier kinetics in this unique organic–inorganic hybrid optoelectronic device. Our work comprehensively evaluates the full potentials of metal halide perovskite as a hole transporting layer by uncovering the positive effect on hole transportation and injection. As a consequence, our findings open up new avenues for the development of efficient carbon dot-based light-emitting diodes.

中文翻译：

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用于高效碳点基发光二极管的工程有机-无机钙钛矿平面异质结

在构建高效薄膜光电器件时，我们一直在努力提高电荷传输和注入的效率。常规使用的有机电荷传输材料的低迁移率和注入能力阻碍了器件性能。在这篇论文中，我们首次展示了金属卤化物钙钛矿可以代替有机物作为空穴传输层来制造高效碳点基发光二极管。有机发光层和下面的钙钛矿层结合形成有机-无机钙钛矿平面异质结，结处的充分接触利用钙钛矿的高电荷迁移率，促进空穴传输和注入。而且，钙钛矿和有机发光层之间的相互作用可以通过控制卤素成分、厚度、表面形态等来设计，有助于器件优化和了解这种独特的有机-无机混合光电器件中的载流子动力学。我们的工作通过揭示对空穴传输和注入的积极影响，全面评估了金属卤化物钙钛矿作为空穴传输层的全部潜力。因此，我们的发现为开发高效的基于碳点的发光二极管开辟了新途径。有助于器件优化和了解这种独特的有机-无机杂化光电器件中的载流子动力学。我们的工作通过揭示对空穴传输和注入的积极影响，全面评估了金属卤化物钙钛矿作为空穴传输层的全部潜力。因此，我们的发现为开发高效的基于碳点的发光二极管开辟了新途径。有助于器件优化和了解这种独特的有机-无机杂化光电器件中的载流子动力学。我们的工作通过揭示对空穴传输和注入的积极影响，全面评估了金属卤化物钙钛矿作为空穴传输层的全部潜力。因此，我们的发现为开发高效的基于碳点的发光二极管开辟了新途径。