Abstract Zinc oxide (ZnO) is probably one of the most researched wide bandgap semiconductors in the last decades due to its unique characteristics in terms of low production cost, high availability, bioinertness, and especially its interesting optical properties. Although this semiconductor is considered an ‘old’ material and is known to possess such unique properties for more than three decades, the interest was renewed because of the advances in nanotechnology and the possibility to be produced in a vast number of nanostructures with tunable properties. An adequate knowledge of the nanomaterials’ optical response is mandatory for assessing and optimizing their functionalities towards different applications. Although the photoluminescence properties of ZnO bulk materials have been known from several decades, quite a number of open questions remains, namely regarding the nature of defects responsible for the broad luminescence bands frequently observed in the visible spectral region. With the effects of reducing the dimensionality of the material to the nanoscale, changes may arise in the luminescence outcome due to the role of the surface/interface characteristics. Indeed, the surface phenomena can strongly affect the nanostructure properties and can be used to tailor them, consequently having a profound influence on the performance of the devices where the nanostructures are employed. Hence, in this article, an overview of the fundamental properties of ZnO, with emphasis on the main optical recombination mechanisms, both in bulk and at the nanoscale, is provided to disclose some of the current knowledge in this subject. In addition, some examples of the myriad of applications where this semiconductor has been exploited are also discussed.

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ZnO微/纳米结构的光致发光研究

摘要氧化锌 (ZnO) 可能是过去几十年中研究最多的宽带隙半导体之一，因为它具有生产成本低、可用性高、生物惰性等独特的特性，尤其是其有趣的光学特性。尽管这种半导体被认为是一种“旧”材料，并且在过去的三十多年中一直被认为具有这种独特的特性，但由于纳米技术的进步以及可以在具有可调特性的大量纳米结构中生产的可能性，这种兴趣重新燃起了。必须充分了解纳米材料的光学响应，才能评估和优化它们在不同应用中的功能。虽然 ZnO 块体材料的光致发光特性已经有几十年的历史了，相当多的悬而未决的问题仍然存在，即关于导致可见光谱区域中经常观察到的宽发光带的缺陷的性质。随着材料维度降低到纳米级的影响，由于表面/界面特性的作用，发光结果可能会发生变化。事实上，表面现象会强烈影响纳米结构的特性，并可用于定制它们，因此对使用纳米结构的器件的性能产生深远的影响。因此，在本文中，提供了对 ZnO 基本特性的概述，重点是主要的光学复合机制，包括体量和纳米级，以揭示该主题的一些当前知识。此外，