| 초록 |
In recent years, organic semiconductor materials, including conjugated oligomers and polymers, have been actively researched for the applications to polymer photovoltaic cells. An efficient photo-induced charge transfer was reported in a polymer thin film consisting of fluorene-based polymers such as poly[9-9’dioctyl-fluorene-co-bithiophene](F8T2). However, despite the ongoing improvement in term of the electronic and photonic properties, most of devices fabricated from polyfluorene type materials in applications of organic light emitting diodes(OLEDs) and organic field effect transistors(OFETs) suffer from degradation as the result of heat treatment and UV irradiation. Recently, a number of reports, especially in applications to OLEDs, have showed that these thermal- or photo-oxidative degradation can be avoided by the introduction of a bulky side group. In this study, we report on a new polyfluorene type copolymer containing a spiroanthracenefluorene to avoid thermal- and photo-oxidative defects, poly[10,10-bis(2-ethylhexyl)-10H-spiro(anthracene-9,9’-fluorene)-co-bithiophene] (SFT2), and device performance of photovoltaic cells consisting of these. |
