报 告 人：Yun Chi（季昀）
（Department of Chemistry, National Tsing Hua University, Taiwan）
报告题目：Chemical Prospective on Phosphorescent Organic Light Emitting Diodes and Dye sensitized Solar Cells
This presentation will first focus on the systematic methodologies for preparation of transition-metal based phosphors that show applications in the field of organic light emitting diodes (OLEDs). We are therefore classified various heteroaromatic chelating ligands according to the types of cyclometalating groups, i.e. either aromatic C-H or azolic N-H fragment, and the adjacent donor fragment that involved in the formation of metallacycles; the latter comprise N-containing heterocycle, N-heterocyclic (NHC) carbene and even diphenylphosphino group. Using the heteroleptic Ir(III) complexes as examples, we then discussed about our strategy of how to prepare the true-blue phosphors.
After then, we shift gear to discuss about our initiative that give a new family of ruthenium(II) complexes suited for DSSC applications. The core design lies in the design of a tridentate bipyridine pyrazolate (bpz) or a functionalized bidentate pyridyl pyrazolate ligand. The respective pyridyl azolate coupled Ru(II) sensitizers were synthesized and characterized. In comparison to N3 and black dye, our modification allowed achievement of increased absorptivity and red-shifting the absorption spectrum. Upon optimization, some of our DSSCs could even produce an efficiency of ~10%, which are comparable to that of the best dye sensitized photovoltaics reported in literature.