光转换材料前沿系列讲座2020年第5期——Jean-Claude Georges Bünzli教授

发布日期:2020-09-30 作者:王育华    编辑:吴婷    来源:

应兰州大学光转换材料与技术国家地方联合工程实验室主任王育华教授邀请,瑞士洛桑联邦理工学院化学科学与工程研究所Jean-Claude Georges Bünzli教授举办线上学术报告。欢迎广大师生届时参加!

题目:Photonic properties and applications of lanthanide molecular materials

报告人:Jean-Claude Georges Bünzli教授

时间:2020930日(周三)下午4:00

线上地点:Zoom(会议ID: 996 438 2910 密码:666666

报告摘要

Lanthanide photonic is a fascinated field that started in 1891 with the invention of the gas mantle by Carl Auer von Welsbach in Austria, made up of 1% cerium oxide doped into thorium oxide. This was followed by the invention of mischmetal, a pyrophoric alloy containing iron and a mixture of light rare earths. Both products are still on sale today and the company founded by Auer is still operating. Present applications range from optical glasses to lasers, optical fibers, phosphors for lighting, and wavelength-converting materials for various applications including bioanalyses and bioimaging as well as solar energy conversion. More advanced applications will include quantum information processing and optical cooling, for instance.

In the 19th century, during which most of the rare earth elements were discovered, several famous scientists contributed to lanthanide photonics, including R. Bunsen and W. Crookes, but one had to wait until the first half of the 20th century before the detailed nature of optical transitions in rare earth compounds started to be understood. Landmarks are the crystal field theory brought forward by Bethe in 1929 and the seminal paper by van Vleck in 1937: “The puzzle of rare-earth spectra in solids” who identified intraconfigurational f-f transitions, as well as interconfigurational d-f transitions. The arduous task of finding, calculating and assigning energy levels in transition metal ions was conducted in the 1940s to 1960s by scientists such as Racah, Wybourne, and Diecke, leading to the establishment of Diecke ‘s diagram. Indeed, the electronic configurations of the trivalent rare earth yield a wealth of energy levels, 16 384 for the fn configurations of the entire series and 180 199 for the fn-1d1 configurations. In parallel, Weissman discovered the sensitization of lanthanide luminescence by surrounding organic ligands in 1942 and Judd and Ofelt rationalized the intensities of the transitions (1953). Since the 1970s, a considerable amount of work has been devoted to understanding spectra and energy transfer processes through sophisticated calculations as well as to investigate higher energy levels and multiphoton excitation. The latter is the heart of upconversion phenomena, evidenced in the 1960s but that have progressively attracted attention since the 1990s and is now ubiquitous in lanthanide photonics thanks to the advent of nanoparticles.

In this seminar, we will discuss the design of highly luminescent compounds, including modeling of energy transfer.

个人简历

Jean-Claude Georges Bünzli,瑞士洛桑联邦理工学院化学科学与工程研究所教授。1971年毕业于瑞士洛桑联邦理工学院并获得博士学位。1974-1980年担任洛桑大学无机和分析化学研究所助理教授;1980-2001 年担任分析和无机化学全职教授。

2001-2010年担任瑞士洛桑联邦理工学院无机化学教授及镧系超分子化学实验室主任。2010年起先后担任了韩国高丽大学、中国科学院福建福州国际科学研究院、香港浸会大学、南方科技大学等一流高校的特聘教授。主要研究方向包括镧系超分子化合物和生物探针的光谱化学性质;近红外、可见光发射镧系化合物的合成与表征;单金属三螺旋配合物和双金属4f-3d4f-4螺旋的自组装;设计荧光生物探针,用于活细胞和癌组织的时间分辨显微镜分析;具有特殊性能的发光材料工程(液晶、离子印迹树脂、电信用塑料材料和光子应用荧光粉)等。