School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China.
Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China.
J Phys Chem Lett. 2022 Sep 15;13(36):8509-8515. doi: 10.1021/acs.jpclett.2c02135. Epub 2022 Sep 6.
Photon upconversion luminescence at the molecule scale is a rarely observed phenomenon despite possessing colossal potential for basic research and reality applications. Here we show that the eight-coordinate erbium molecular complex composed of Er ion, dibenzoylmethane, and 2,2'-bipyridine exhibits upconversion emission. Under direct excitation at the absorption band of Er ion at 980 nm, the complex shows upconverted green emissions of Er ion at 525 and 545 nm at room temperature. Noticeably, upon the introduction of fluoride ions into this complex, an additional upconverted red emission at 667 nm appears as well, and the luminescence intensities of both the green and red emissions increase by a factor of 13 at most. This study not only provides a strategy to adjust the green and red emissions in mononuclear erbium complexes but also broadens the horizons of designing lanthanide-based molecular upconversion systems.
尽管在基础研究和实际应用方面具有巨大的潜力，但分子尺度上的光上转换发光现象仍然很少见。在这里，我们展示了由铒离子、二苯甲酰甲烷和 2,2'-联吡啶组成的八配位铒分子配合物表现出上转换发射。在 980nm 的铒离子吸收带的直接激发下，该配合物在室温下显示出铒离子的上转换绿光发射，波长分别为 525nm 和 545nm。值得注意的是，当将氟离子引入该配合物中时，还会出现另外一个上转换红光发射，波长为 667nm，并且绿光和红光发射的发光强度最高增加了 13 倍。这项研究不仅提供了一种调节单核铒配合物中绿光和红光发射的策略，而且拓宽了设计基于镧系元素的分子上转换系统的视野。
