Lanthanide-doped upconversion nanomaterials are well known for converting near-infrared (NIR) excitation photons into visible, ultraviolet, and NIR emission photons. Excitation of NIR light offers low autofluorescence background and high penetration depth in biological environments due to the reduced light scattering. Consequently, these have attracted considerable interest because their exceptional optical properties have led to applications in diverse areas such as bioassays, biomedical imaging, and forensics; these properties are, namely: large anti-Stokes shifts, sharp emission spectra and long excited-state lifetimes. The nanomaterials can be utilized for a variety of applications including detection of various analytes, bioimaging, therapies, energy conversion, and security. In this review, we briefly describe the upconversion luminescence process, effective synthetic approaches, and recent literature that elucidate the exceptional properties of these materials and its applications.

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镧系掺杂上转换纳米材料的最新进展和应用

掺杂镧系元素的上转换纳米材料是众所周知的，用于将近红外（NIR）激发光子转换为可见光，紫外光和NIR发射光子。由于减少了光散射，在生物环境中，近红外光的激发提供了低自发荧光背景和高穿透深度。因此，这些技术引起了极大的兴趣，因为它们出色的光学性能已导致在生物测定，生物医学成像和法医等各个领域的应用。这些特性分别是：大的反斯托克斯位移，清晰的发射光谱和长的激发态寿命。纳米材料可用于多种应用，包括各种分析物的检测，生物成像，疗法，能量转换和安全性。在这篇评论中