Progress in Polymer Science 37 (2012) 1192–1264 Contents lists available at SciVerse ScienceDirect Progress in Polymer Science j ourna l ho me p ag e: www.elsevier.com/locate/ppolysci Polyﬂuorene-based semiconductors combined with various periodic table elements for organic electronics Ling-Hai Xie, Cheng-Rong Yin, Wen-Yong Lai, Qu-Li Fan, Wei Huang ∗ Key Laboratory for Organic Electronics & Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications (NUPT), Nanjing 210046, China a r t i c l e i n f o Article history: Received 12 April 2011 Received in revised form 8 February 2012 Accepted 10 February 2012 Available online 16 February 2012 Keywords: -Conjugated polymers Band-gap engineering Light-emitting diodes Photovoltaic cell Field-effect transistors Memories a b s t r a c t Polyﬂuorenes have emerged as versatile semiconducting materials with applications in various polymer optoelectronic devices, such as light-emitting devices, lasers, solar cells, memories, ﬁeld-effect transistors and sensors. Organic syntheses and polymerizations allow for the powerful introduction of various periodic table elements and their build- ing blocks into -conjugated polymers to meet the requirements of organic devices. In this review, a soccer-team-like framework with 11 nodes is initially proposed to illus- trate the structure–property relationships at three levels: chain structures, thin ﬁlms and devices. Second, the modelling of hydrocarbon polyﬂuorenes (CPFs) is summarized within the framework of a four-element design principle, in which we have highlighted polymorphic poly(9,9-dialkylﬂuorene)s with unique supramolecular interactions, various hydrocarbon-based monomers with different electronic structures, functional bulky groups with steric hindrance effects and ladder-type, kinked, hyperbranched and dendritic confor- mations. Finally, the detailed electronic structure designs of main-chain-type heteroatomic copolyﬂuorenes (HPFs) and metallopolyﬂuorenes (MPFs) are described in the third and fourth sections. Supramolecular, nano and soft semiconductors are the future of polyﬂuo- renes in the ﬁelds of optoelectronics, spintronics and electromechanics. © 2012 Elsevier Ltd. All rights reserved. Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1194 1.1. Background and scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1194 1.2. Basic knowledge and principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1195 1.2.1. Performance and stability of polymer devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1196 1.2.2. Optoelectronic property and morphology of semiconducting polymer ﬁlms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1197 1.2.3. Four-element design of semiconducting polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1199 2. Hydrocarbon polyﬂuorenes (CPFs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1202 2.1. Poly(9,9-dialkylﬂuorene)s (PDAFs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1202 2.2. Polyﬂuorenes with hydrocarbon-based -conjugated monomers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1204 2.3. Polyﬂuorenes substituted with various bulky groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1206 2.4. Fused and ladder-type polyﬂuorenes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1207 2.5. Polyﬂuorenes with kinked conformations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1208 2.6. Hyperbranched and dendritic polyﬂuorenes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1209 ∗ Corresponding author. Tel.: +86 25 8586 6008; fax: +86 25 8586 6999. E-mail address: iamwhuang@njupt.edu.cn (W. Huang). 0079-6700/$ – see front matter © 2012 Elsevier Ltd. All rights reserved. doi:10.1016/j.progpolymsci.2012.02.003