Lanthanide-doped upconversion nanoparticles are undergoing extensive investigations in many fields, particularly in biophotonics and photophysics. In an attempt to boost upconversion emission intensities, Yb-based fluoride crystals have been recently identified as more efficient alternatives to classical NaYF₄ crystals. Yb-Based fluoride crystals featuring a maximal occupancy of the host lattice by Yb³⁺ sensitizers facilitate the utilization of excitation light and promote energy transfer to upconverting activators, which contributes to a significant enhancement of upconversion luminescence. In this article, we present a survey of recent studies on chemical preparations of Yb-based fluoride nanoparticles with well-defined size and morphology. We show that these Yb-based upconversion nanoparticles are playing important roles in a few emerging applications such as optogenetics, biodetection and upconversion lasing.

中文翻译：

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Yb基氟化物上转换纳米粒子的合成及应用的最新进展

掺杂镧系元素的上转换纳米粒子在许多领域，特别是在生物光子学和光物理领域，正在接受广泛的研究。为了提高上转换发射强度，最近发现基于Yb的氟化物晶体是经典NaYF ₄晶体的更有效替代物。基于Yb的氟化物晶体，具有Yb ³⁺对主体晶格的最大占有率敏化剂有助于激发光的利用，并促进能量转移到上转换活化剂，这有助于上转换发光的显着增强。在本文中，我们对具有明确定义的尺寸和形态的基于Yb的氟化物纳米粒子的化学制备方法进行了最新研究。我们表明，这些基于Yb的上转换纳米粒子在诸如光遗传学，生物检测和上转换激光等一些新兴应用中起着重要作用。