Clouds in the sky pass almost 80% of ultraviolet (UV) radiation to the earth's surface, which has a significant impact on humankind. Conventional UV photodetectors (PDs) require an external battery, which not only increases the device size but also has a limited life span and maintenance costs can be prohibitively expensive. An alternative and more technically-sound solution would be the use of self-powered UV PDs that can operate independently, eliminating the need for an external source. Although many exciting studies have been done and state-of-the-art research is underway to successfully fabricate self-powered UV PDs, periodic reviews on this topic are deemed essential so that the technology's readiness can be properly evaluated and critical challenges can be addressed in a timely manner. In this article, the key issues and most exciting developments made in recent years on built-in electric field assisted self-powered UV PDs based on p–n homojunctions, p–n heterojunctions, and Schottky junctions followed by energy harvester integrated UV PDs are extensively reviewed. Finally, a summary and comparison of different types of self-powered UV PDs as well as future challenges that need to be addressed are discussed. This review sets a foundation providing essential insights into the present status of self-powered UV PDs with which researchers can engage and deal with the major challenges.

中文翻译：

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紫外光传感：从传统到自供电光电探测器的转变

天空中的云层将近 80% 的紫外线 (UV) 辐射传递到地球表面，这对人类产生了重大影响。传统的紫外线光电探测器 (PD) 需要外部电池，这不仅会增加设备尺寸，而且使用寿命有限，而且维护成本可能非常昂贵。另一种技术上更可靠的解决方案是使用可以独立运行的自供电 UV PD，从而消除对外部源的需求。尽管已经完成了许多令人兴奋的研究并且正在进行最先进的研究以成功制造自供电 UV PD，但对该主题的定期审查被认为是必不可少的，以便可以正确评估技术的准备情况并可以解决关键挑战及时。在本文中，近年来，基于 p-n 同质结、p-n 异质结和肖特基结以及能量收集器集成 UV PD 的内置电场辅助自供电 UV PD 的关键问题和最激动人心的发展得到了广泛的审查。最后，讨论了不同类型的自供电 UV PD 的总结和比较以及未来需要解决的挑战。这篇综述奠定了基础，为研究人员可以参与和应对主要挑战的自供电 UV PD 的现状提供了重要的见解。讨论了不同类型的自供电 UV PD 的总结和比较以及需要解决的未来挑战。这篇综述奠定了基础，为研究人员可以参与和应对主要挑战的自供电 UV PD 的现状提供了重要的见解。讨论了不同类型的自供电 UV PD 的总结和比较以及需要解决的未来挑战。这篇综述奠定了基础，为研究人员可以参与和应对主要挑战的自供电 UV PD 的现状提供了重要的见解。