| 초록 |
Polymer-based photovoltaic cells have seen a tremendous improvement in both device efficiency and understanding of the underlying physical processes. In order to enhance efficiencies even further, research activities for new materials are needed with better aligned energy levels. One interesting approach is by narrowing the donor band gap to enhance light absorption. Lower band gap values also result in enhanced thermal population of the conduction band, thus increasing the number of intrinsic charge carrier, and the lower oxidation potential associated with a low Eg can result in the stabilization of corresponding doped ( i.e,. oxidized) state. We synthesized perylene diimide derivatives (PDIs) based copolymer as a donor, because PDIs have large molar absorption coefficients, good electron accepting properties and possible generation of a highly conducting direction along the pp stacking axis,6,7 in addition to the other merits, like robust, thermally stable, and inexpensive. |
