Harvesting of near infrared (NIR) light in the abundant and environmentally friendly solar spectrum is particularly significant to enhance the utilization rate of the cleanest energy on earth. Appreciating the unique nonlinear optical properties of upconversion materials for converting low-energy incident light into high-energy radiation, they become the most promising candidates for fabricating NIR light-active photocatalytic systems by integrating with semiconductors. The present review summarizes recent NIR light-active photocatalytic systems based on a sequence of NaYF₄-based, fluoride-based, oxide-based and Ln³⁺ ion-doped semiconductor-based photocatalysts for degradation of organic molecules. In addition, we provide an in-depth analysis of various photocatalytic mechanisms and enhancement effects for efficient photo-redox performance of different upconversion semiconductor photocatalysts. We envision that this review can inspire multidisciplinary research interest in rational design and fabrication of efficient full-spectrum active (UV-visible-NIR) photocatalytic systems and their wider applications in solar energy conversion.

中文翻译：

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NIR光活化上转换半导体光催化剂

收集丰富且环保的太阳光谱中的近红外（NIR）光对于提高地球上最清洁能源的利用率尤其重要。它们具有将低能入射光转换成高能辐射的上转换材料独特的非线性光学特性，因此成为与半导体集成制造NIR光活性光催化系统的最有希望的候选者。本综述总结了基于一系列基于NaYF _4，基于氟化物，基于氧化物和Ln ^3+的NIR光活性光催化系统离子掺杂的基于半导体的光催化剂，可降解有机分子。此外，我们提供了各种光催化机理和增强效应的深入分析，以提高不同上转换半导体光催化剂的有效光氧化还原性能。我们认为，这篇综述可以激发多学科研究兴趣，以进行合理设计和制造高效的全光谱活性（UV-visible-NIR）光催化系统及其在太阳能转换中的广泛应用。