Molecular orientation of regioregular poly(3-hexylthiophene) film

レジオレギュラーポリ(3-ヘキシルチオフェン)膜の分子配向

池浦 広美*; 関口 哲弘  

Ikeura, Hiromi*; Sekiguchi, Tetsuhiro

ドナー有機半導体であるポリ(3-ヘキシルチオフェン)(P3HT)主軸のレジオレギュラリティー(頭尾結合様式の完全性)は分子配向をコントロールするうえで重要な因子であり、有機太陽電池の性能に大きく影響を及ぼすと考えられる。本研究は溶液法によりレジオレギュラー(RR-) P3HTの配向薄膜をシリコン基板上に形成し、その配向構造を角度分解X線吸収端微細構造(NEXAFS)法により調べた。最低空軌道エネルギー(LUMO)をS 1s吸収端エネルギーから得て、エネルギー変換効率を求め、アモルファスP3HT薄膜と比較した。

The regioregularity (2head-to-5'tail regularity) for organic semiconductor polymer backbone plays a dominant role in controlling molecular orientation, thus strongly influences the performance of organic solar cells. In the present work, we have investigated the orientation structure of donor regioregular poly(3-hexylthiophene) (P3HT) films using angle-resolved near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy. The films on silicon substrates were prepared by solution spin cast method. The lowest unoccupied molecular orbital (LUMO) levels were obtained from the edge energies of S 1s inner-shell excitation, from which energy conversion efficiencies for solar cells were estimated. The results of them were compared with those which were measured for amorphous P3HT films.