SEMINAR

Light Absorption and Emission in Molecular Solids

Soo Young Park

Department of Materials Science and Engineering, Seoul National University,
1 Gwanak-ro, Gwanak-gu, Seoul 151-744, Korea
parksy@snu.ac.kr

Over last years, we have developed several different classes of π-conjugated molecular scaffolds for controlled light absorption, emission and charge transport. In this presentation, I will speak about four specific molecular scaffolds in terms of the molecular design, supramolecular stacking, photophysical and transport properties. First part is about the floppy molecules comprising the cyanostilbene units which show the strong self-assembly, solid state luminescence enhancement (SLE), and also the outstanding performances in OFET and OSC devices. Second and third classes of molecules are novel heteroarene scaffolds incorporating the indoloindole (IDID) and naphthyridinedione (NTD) units, respectively. Application of these molecules to the high performance OFET semiconductor, HTM in perovskite solar cell, and OLED emitter will be demonstrated. Fourth class of molecules are 2-hydroxyphenylimidazole derivatives which show the excited state intramolecular proton transfer (ESIPT) behavior. Entirely new disciplines of ‘molecular pixel’ and color-specific fluorescence switching are demonstrated with these ESIPT molecules.