3,4-Disubstituted Polyalkylthiophenes for High-Performance Thin-Film Transistors and Photovoltaics

详细信息    查看全文

• 作者：Sangwon Ko ; Eric Verploegen ; Sanghyun Hong ; Rajib Mondal ; Eric T. Hoke ; Michael F. Toney ; Michael D. McGehee ; Zhenan Bao
• 刊名：Journal of the American Chemical Society
• 出版年：2011
• 出版时间：October 26, 2011
• 年：2011
• 卷：133
• 期：42
• 页码：16722-16725
• 全文大小：745K
• 年卷期：v.133,no.42(October 26, 2011)
• ISSN：1520-5126

文摘

We demonstrate that poly(3,4-dialkylterthiophenes) (P34ATs) have comparable transistor mobilities (0.17 cm² V^鈥? s^鈥?) and greater environmental stability (less degradation of on/off ratio) than regioregular poly(3-alkylthiophenes) (P3ATs). Unlike poly(3-hexylthiophene) (P3HT), P34ATs do not show a strong and distinct 蟺鈥撓€ stacking in X-ray diffraction. This suggests that a strong 蟺鈥撓€ stacking is not always necessary for high charge-carrier mobility and that other potential polymer packing motifs in addition to the edge-on structure (蟺鈥撓€ stacking direction parallel to the substrate) can lead to a high carrier mobility. The high charge-carrier mobilities of the hexyl and octyl-substituted P34AT produce power conversion efficiencies of 4.2% in polymer:fullerene bulk heterojunction photovoltaic devices. An enhanced open-circuit voltage (0.716鈥?.771 eV) in P34AT solar cells relative to P3HT due to increased ionization potentials was observed.