对称性和刚性,以促进基于的分子升光转化在溶液中的作用
Soroush Naseri1, Inès Taarit1, Hélène Bolvin2
1Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, 1211, Geneva 4, Switzerland.
Angewandte Chemie (International ed. in English)
|October 17, 2023
概括
稳定,低对称的分子复合体显著增强光的向上转换. 这一突破将近红外到可见绿光的转换效率提高了多达1000倍,为光学应用开辟了新的可能性.
科学领域:
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
- 光物理学的光学物理学
背景情况:
- 单中心分子上转化以前仅限于高度对称的同质复合体,如[Er(Lk) 3+ .
- 兴奋状态吸收 (ESA) 机制是向上转换的关键,但需要优化分子设计.
- 开发稳定,低对称性的异质感应 adducts 对于提高性能至关重要.
研究的目的:
- 设计和合成新型异构体复合体,[LkEr(hfa) 3),以增强单中心向上转换.
- 研究连接体特性 (π电子移位,灵活性,重原子效应) 对上转换效率的影响.
- 为了实现近红外到可见绿光转换产量的显著提升.
主要方法:
- 合成异体质复合物[LkEr(hfa) 3 ,其中Lk是多芳香的三酸连接体,hfa-是六乙烯酸.
- 合成复合物的表征.
- 在室温下使用线性光学测量上转化量子产量,监测801nm (NIR) 到542nm (绿) 的辐射.
主要成果:
- 成功合成了稳定,低对称性的异构体复合体 [LkEr(hfa) 3].
- 证明了上转换量子收益率的显著提高,高达三次数量级 (1000x).
- 相关联观察到的效率提升与联结体属性:扩展π电子移位,灵活性和重原子效应.
结论:
- 低对称性的异体质复合体[LkEr(hfa) 3]在分子上升转换方面优于以前的同体质设计.
- 连接体设计在优化激发状态吸收和促进NIR到可见光转换方面发挥着关键作用.
- 这些发现为更高效的基于分子的光学上转换技术铺平了道路.
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