Largely enhanced efficiency in ZnO nanowire/p-polymer hybridized inorganic/organic ultraviolet light-emitting diode by piezo-phototronic effect.
Largely enhanced efficiency in ZnO nanowire/p-polymer hybridized inorganic/organic ultraviolet light-emitting diode by piezo-phototronic effect.
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DOI：
10.1021/nl304163n
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发表时间：
2013-01
期刊：
影响因子：
10.8
通讯作者：
Qing Yang;Y. Liu;Caofeng Pan;Jun Chen;X. Wen;Zhong Lin Wang
中科院分区：
文献类型：
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作者：
Qing Yang;Y. Liu;Caofeng Pan;Jun Chen;X. Wen;Zhong Lin Wang
ZnO纳米线无机/有机混合紫外（UV）发光二极管（LED）吸引了相当大的关注，因为它们不仅联合收割机了聚合物的高柔性与无机纳米结构的结构和化学稳定性，而且具有比薄膜结构更高的光提取效率。然而，迄今为止，基于ZnO纳米结构的紫外LED的外量子效率受到缺乏有效方法来实现电子贡献电流和空穴贡献电流之间的平衡以减少界面处非辐射复合的限制。在这里，我们证明了压电光电效应可以大大提高效率的杂化无机/有机LED的ZnO纳米线/p-聚合物结构制成的，通过修剪的电子电流，以匹配的空穴电流，并增加本地化的空穴密度附近的界面，通过载流子通道所产生的压电极化电荷的ZnO侧。在施加适当的应变后，混合LED的外部效率提高了至少2倍，达到5.92%。这项研究为提高有机LED效率提供了一个新的概念，并具有广泛的高性能柔性光电器件的巨大潜力。
ZnO nanowire inorganic/organic hybrid ultraviolet (UV) light-emitting diodes (LEDs) have attracted considerable attention as they not only combine the high flexibility of polymers with the structural and chemical stability of inorganic nanostructures but also have a higher light extraction efficiency than thin film structures. However, up to date, the external quantum efficiency of UV LED based on ZnO nanostructures has been limited by a lack of efficient methods to achieve a balance between electron contributed current and hole contributed current that reduces the nonradiative recombination at interface. Here we demonstrate that the piezo-phototronic effect can largely enhance the efficiency of a hybridized inorganic/organic LED made of a ZnO nanowire/p-polymer structure, by trimming the electron current to match the hole current and increasing the localized hole density near the interface through a carrier channel created by piezoelectric polarization charges on the ZnO side. The external efficiency of the hybrid LED was enhanced by at least a factor of 2 after applying a proper strain, reaching 5.92%. This study offers a new concept for increasing organic LED efficiency and has a great potential for a wide variety of high-performance flexible optoelectronic devices.