Lecture by Prof. Xiaoji Xie from Nanjing Tech University

                Source:理學院英文網  Time:2019-09-11  Page Views:16

                Prof. Xiaoji Xie from Nanjing Tech University visited School of Science on August 28 and gave a lecture titled “Upconversion Nanoparticles: Luminescence Enhancement and Excitation Tuning”.

                Lanthanide-doped upconversion nanoparticles hold great promise for various applications, ranging from bioimaging and optogenetics to lasing and 3D display, due to their featured properties including excellent photostability, continuous emission capability, and sharp multi-peak line emission. Despite recent advances in upconversion nanoparticles, they still suffer from many challenges, such as weak luminescence intensity, strong luminescence quenching, limited functions, as well as confined excitation and emission ranges. For example, for upconversion nanoparticles in aqueous solvents, one of the main issues is the strong absorption of ~980 nm excitation energy caused by the –OH group, which quenches the upconversion emission and induces serious photothermal effect during bioapplications. In this lecture, Prof. Xie showed several potential ways to enhance the upconversion emission of upconversion nanoparticles. He also demonstrated approaches to manipulate the excitation wavelength of upconversion nanoparticles, extending both the excitation and emission ranges of upconversion nanoparticles. Meanwhile, a recent example using upconversion nanoparticles for fabricating multifunctional nanocomposites was discussed. Finally, Prof. Xie gave a few examples to show that the luminescence quenching of upconversion nanoparticles (lanthanide ions) may not always have adverse effects and such luminescence quenching can be used for sensing and developing new functional materials.