Electro-optical properties of confined structured multilayer films prepared by the spin-assembly method

POLY 215

Hosub Kim, School of Chemical and Biological Engineering, NANO Systems Institute, Seoul National University, Seoul, 151-744, South Korea, Jinhan Cho, School of Advanced Materials, Kookmin University, 861-1 Jeongneung-dong, Songbuk-gu, Seoul, 136-702, South Korea, Dong Young Kim, OptoElectronic Materials Research Center, Korea Institute of Science and Technology, Seoul, South Korea, and Kookheon Char, School of Chemical and Biological Engineering and NANO Systems Institute - National Core Research Center, Seoul National University, Seoul, 151-744, South Korea.
Multilayer films composed of poly(p-phenylene vinylene) (PPV) and poly(methacrylic acid) (PMAA) were fabricated by spin-assembly method. These films, comprising a confined layer structure, showed that the water contact angles are periodically oscillated when the top surface layer is alternated between PPV precursor and PMAA. Furthermore, the emission peaks in the photoluminescence and electroluminescence spectra of these devices were strongly blue-shifted due to excitons formed at the confined PPV layers. Particularly when inserting about 1.0 nm thick PMAA layers, which possibly induced a tunneling effect on the carriers, these multilayer films decreased the mobility of the hole carriers in the PPV layers, and therefore increased the recombination probability in the emitting layer with confined geometry. As a result, the device efficiency was significantly improved in comparison with that of a PPV single layer device and with that of devices with relatively thick PMAA layers of 1.4 or 2.0 nm.
 

General Papers: Polymers in Nanotechnology
6:00 PM-8:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Polymer Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007