Synthesis of all-conjugated poly(3-hexylthiophene)-block- poly(3-(4'-(3

New all-conjugated block copolythiophene, poly(3- hexylthiophene)-block-poly(3-(4 0 -(3 00 ,7 00 -dimethyloctyloxy)-3 0 -pyr- idinyl)thiophene) (P3HT-b-P3PyT) was successfully prepared by Grignard metathesis polymerization. The supramolecular inter- action between (6,6)-phenyl-C61-butyric acid methyl ester (PCBM) and P3PyT was proposed to control the aggregated size of PCBM and long-term thermal stability of the photovol- taic cell, as evidenced by differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and optical mi- croscopy. The effect of different solvents on the electronic and optoelectronic properties was studied, including chloroform (CL), dichlorobenzene (DCB), and mixed solvent of CL/DCB. The optimized bulk heterojunction solar cell devices using the P3HT-b-P3PyT/PCBM blend showed a power conversion effi- ciency of 2.12%, comparable to that of P3HT/PCBM device de- spite the fact that former had a lower crystallinity or absorption coefficient. Furthermore, P3HT-b-P3PyT could be also used as a surfactant to enhance the long-term thermal stability of P3HT/ PCBM-based solar cells by limiting the aggregated size of PCBM. This study represents a new supramolecular approach to design all-conjugated block copolymers for high-performance photovoltaic devices. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 2577-2587, 2011

[1]  Wen‐Chang Chen,et al.  Conjugated rod–coil block copolymers: Synthesis, morphology, photophysical properties, and stimuli-responsive applications , 2011 .

[2]  Samson A. Jenekhe,et al.  One-Dimensional Nanostructures of π-Conjugated Molecular Systems: Assembly, Properties, and Applications from Photovoltaics, Sensors, and Nanophotonics to Nanoelectronics† , 2011 .

[3]  Tomoya Higashihara,et al.  Synthesis and Characterization of Polythiophenes Bearing Aromatic Groups at the 3-Position , 2011 .

[4]  Sung‐Ho Jin,et al.  Synthesis of Three New 1-(2,6-Diisopropylphenyl)-2,5-di(2-thienyl) pyrrole-Based Donor Polymers and Their Bulk Heterojunction Solar Cell Applications , 2010 .

[5]  S. Jenekhe,et al.  Regioregular poly(3‐alkanoylthiophene): Synthesis and electrochemical, photophysical, charge transport, and photovoltaic properties , 2010 .

[6]  Cheng-Liang Liu,et al.  Synthesis, Morphology, and Properties of Poly(3‐hexylthiophene)‐block‐Poly(vinylphenyl oxadiazole) Donor–Acceptor Rod–Coil Block Copolymers and Their Memory Device Applications , 2010 .

[7]  W. Su,et al.  Facile Syntheses, Morphologies, and Optical Absorptions of P3HT Coil-Rod-Coil Triblock Copolymers , 2010 .

[8]  So-Jung Park,et al.  Highly tunable photoluminescent properties of amphiphilic conjugated block copolymers. , 2010, Journal of the American Chemical Society.

[9]  Wen‐Chang Chen,et al.  Enhancement of P3HT/PCBM Photovoltaic Efficiency Using the Surfactant of Triblock Copolymer Containing Poly(3-hexylthiophene) and Poly(4-vinyltriphenylamine) Segments , 2010 .

[10]  Ashlee A. Jahnke,et al.  Controlling phase separation and optical properties in conjugated polymers through selenophene-thiophene copolymerization. , 2010, Journal of the American Chemical Society.

[11]  Tomoya Higashihara,et al.  Preparation of Nanoporous Poly(3-hexylthiophene) Films Based on a Template System of Block Copolymers via Ionic Interaction , 2010 .

[12]  Zhiqun Lin,et al.  Self-assembly of all-conjugated poly(3-alkylthiophene) diblock copolymer nanostructures from mixed selective solvents. , 2010, ACS nano.

[13]  S. Jenekhe,et al.  Enhanced Performance of Bulk Heterojunction Solar Cells Using Block Copoly(3-alkylthiophene)s , 2010 .

[14]  R. Mezzenga,et al.  A New Supramolecular Route for Using Rod‐Coil Block Copolymers in Photovoltaic Applications , 2010, Advanced materials.

[15]  R. Mezzenga,et al.  Poly(3‐hexylthiophene)‐b‐poly(3‐cyclohexylthiophene): Synthesis, microphase separation, thin film transistors, and photovoltaic applications , 2010 .

[16]  Youngmin Lee,et al.  Facile Synthesis of Well-Defined Coil−Rod−Coil Block Copolymer Composed of Regioregular Poly(3-hexylthiophene) via Anionic Coupling Reaction , 2010 .

[17]  Tomoya Higashihara,et al.  Synthesis of block copolymers consisting of poly(3-hexylthiophene) and polystyrene segments through ionic interaction and their self-assembly behavior , 2010 .

[18]  V. Bocharova,et al.  Synthesis of a Bifunctional Initiator for Controlled Kumada Catalyst-Transfer Polycondensation/Nitroxide-Mediated Polymerization and Preparation of Poly(3-hexylthiophene)−Polystyrene Block Copolymer Therefrom , 2010 .

[19]  Wen‐Chang Chen,et al.  All-conjugated diblock copolymer of poly(3-hexylthiophene)-block-poly(3-phenoxymethylthiophene) for field-effect transistor and photovoltaic applications , 2009 .

[20]  M. Andersson,et al.  A planar copolymer for high efficiency polymer solar cells. , 2009, Journal of the American Chemical Society.

[21]  Chain‐Shu Hsu,et al.  Synthesis of conjugated polymers for organic solar cell applications. , 2009, Chemical reviews.

[22]  Tomoya Higashihara,et al.  Living Anionic Polymerization of 4-Vinyltriphenylamine for Synthesis of Novel Block Copolymers Containing Low-Polydisperse Poly(4-vinyltriphenylamine) and Regioregular Poly(3-hexylthiophene) Segments , 2009 .

[23]  Tomoya Higashihara,et al.  Synthesis and characterization of a novel coil–rod–coil triblock copolymers comprised of regioregular poly(3-hexylthiophene) and poly(methyl methacrylate) segments , 2009 .

[24]  Guillermo C Bazan,et al.  "Plastic" solar cells: self-assembly of bulk heterojunction nanomaterials by spontaneous phase separation. , 2009, Accounts of chemical research.

[25]  R. Mezzenga,et al.  Crystalline Diblock Conjugated Copolymers: Synthesis, Self-Assembly, and Microphase Separation of Poly(3-butylthiophene)-b-poly(3-octylthiophene) , 2009 .

[26]  Wen‐Chang Chen,et al.  Synthesis of New Indolocarbazole-Acceptor Alternating Conjugated Copolymers and Their Applications to Thin Film Transistors and Photovoltaic Cells , 2009 .

[27]  T. Emrick,et al.  Donor−Acceptor Poly(thiophene-block-perylene diimide) Copolymers: Synthesis and Solar Cell Fabrication , 2009 .

[28]  Luping Yu,et al.  Development of new semiconducting polymers for high performance solar cells. , 2009, Journal of the American Chemical Society.

[29]  T. Kowalewski,et al.  Regioregular Poly(3-hexylthiophene) in a Novel Conducting Amphiphilic Block Copolymer. , 2009, Macromolecular rapid communications.

[30]  C. Hawker,et al.  A high purity approach to poly(3‐hexylthiophene) diblock copolymers , 2008 .

[31]  H. Martínez,et al.  Diblock and Random Donor/Acceptor "Double Cable" Polythiophene Copolymers Via the GRIM Method , 2008 .

[32]  Tomoya Higashihara,et al.  Facile Synthesis of ABA Triblock Copolymer Containing Regioregular Poly(3-hexylthiophene) and Polystyrene Segments via Linking Reaction of Poly(styryl)lithium , 2008 .

[33]  Andreas W. Liehr,et al.  High throughput testing platform for organic Solar Cells , 2008 .

[34]  D. Venkataraman,et al.  Protocols for Efficient Postpolymerization Functionalization of Regioregular Polythiophenes , 2008 .

[35]  T. Verbiest,et al.  Transfer of supramolecular chirality in block copoly(thiophene)s. , 2008, Chemistry.

[36]  M. Thelakkat,et al.  Crystalline-crystalline donor-acceptor block copolymers. , 2008, Angewandte Chemie.

[37]  C. Dagron-Lartigau,et al.  Photovoltaic cells based on polythiophenes carrying lateral phenyl groups , 2008 .

[38]  E. Diau,et al.  Intramolecular Donor–Acceptor Regioregular Poly(3‐hexylthiophene)s Presenting Octylphenanthrenyl‐Imidazole Moieties Exhibit Enhanced Charge Transfer for Heterojunction Solar Cell Applications , 2008 .

[39]  Yongfang Li,et al.  Conjugated Polymer Photovoltaic Materials with Broad Absorption Band and High Charge Carrier Mobility , 2008 .

[40]  B. Olsen,et al.  Self-assembly of rod–coil block copolymers , 2008 .

[41]  R. Mezzenga,et al.  Self-Assembly of Rod-Coil Block Copolymers for Photovoltaic Applications , 2008 .

[42]  M. Ueda,et al.  Well-Controlled Synthesis of Block Copolythiophenes , 2008 .

[43]  Gang Li,et al.  Effects of Solvent Mixtures on the Nanoscale Phase Separation in Polymer Solar Cells , 2008 .

[44]  K. Hashimoto,et al.  Synthesis of all-conjugated diblock copolymers by quasi-living polymerization and observation of their microphase separation. , 2008, Journal of the American Chemical Society.

[45]  Samson A Jenekhe,et al.  Highly efficient solar cells based on poly(3-butylthiophene) nanowires. , 2008, Journal of the American Chemical Society.

[46]  C. Frisbie,et al.  Nanoporous Poly(3-alkylthiophene) Thin Films Generated from Block Copolymer Templates , 2008 .

[47]  E. Thomas,et al.  Crystalline Structure in Thin Films of DEH−PPV Homopolymer and PPV-b-PI Rod−Coil Block Copolymers , 2008 .

[48]  J. Fréchet,et al.  Polymer-fullerene composite solar cells. , 2008, Angewandte Chemie.

[49]  T. Yokozawa,et al.  Catalyst-Transfer Condensation Polymerization for the Synthesis of Well-Defined Polythiophene with Hydrophilic Side Chain and of Diblock Copolythiophene with Hydrophilic and Hydrophobic Side Chains , 2007 .

[50]  Mario Leclerc,et al.  A Low‐Bandgap Poly(2,7‐Carbazole) Derivative for Use in High‐Performance Solar Cells , 2007 .

[51]  A J Heeger,et al.  Efficiency enhancement in low-bandgap polymer solar cells by processing with alkane dithiols. , 2007, Nature materials.

[52]  R. Mezzenga,et al.  Weakly segregated smectic C lamellar clusters in blends of rods and rod-coil block copolymers , 2007 .

[53]  Robin H. A. Ras,et al.  Control of self-assembly by charge-transfer complexation between C60 fullerene and electron donating units of block copolymers , 2006 .

[54]  J. D’Haen,et al.  Tuning the Dimensions of C60‐Based Needlelike Crystals in Blended Thin Films , 2006 .

[55]  Mats Andersson,et al.  Influence of Solvent Mixing on the Morphology and Performance of Solar Cells Based on Polyfluorene Copolymer/Fullerene Blends , 2006 .

[56]  Donal D. C. Bradley,et al.  A strong regioregularity effect in self-organizing conjugated polymer films and high-efficiency polythiophene:fullerene solar cells , 2006 .

[57]  T. Yokozawa,et al.  Catalyst-transfer polycondensation. mechanism of Ni-catalyzed chain-growth polymerization leading to well-defined poly(3-hexylthiophene). , 2005, Journal of the American Chemical Society.

[58]  R. D. Mccullough,et al.  Facile Synthesis of End-Functionalized Regioregular Poly(3-alkylthiophene)s via Modified Grignard Metathesis Reaction , 2005 .

[59]  Yang Yang,et al.  High-efficiency solution processable polymer photovoltaic cells by self-organization of polymer blends , 2005 .

[60]  R. Gil,et al.  Experimental evidence for the quasi-living nature of the grignard metathesis method for the synthesis of regioregular poly(3-alkylthiophenes) , 2005 .

[61]  C. P. Radano,et al.  Crystalline-crystalline block copolymers of regioregular poly(3-hexylthiophene) and polyethylene by ring-opening metathesis polymerization. , 2005, Journal of the American Chemical Society.

[62]  Xiaoniu Yang,et al.  Nanoscale morphology of high-performance polymer solar cells. , 2005, Nano letters.

[63]  R. D. Mccullough,et al.  In‐Situ End‐Group Functionalization of Regioregular Poly(3‐alkylthiophene) Using the Grignard Metathesis Polymerization Method , 2004 .

[64]  Tsutomu Yokozawa,et al.  Chain-growth polymerization for poly(3-hexylthiophene) with a defined molecular weight and a low polydispersity , 2004 .

[65]  E. van Veenendaal,et al.  Solution-processed ambipolar organic field-effect transistors and inverters , 2003, Nature materials.

[66]  D. Moses,et al.  Templating Organic Semiconductors via Self-Assembly of Polymer Colloids , 2003, Science.

[67]  Compositional and orientational ordering in rod-coil diblock copolymer melts , 2001, cond-mat/0110143.

[68]  Robert S. Loewe,et al.  A Simple Method to Prepare Head‐to‐Tail Coupled, Regioregular Poly(3‐alkylthiophenes) Using Grignard Metathesis , 1999 .

[69]  J. Hummelen,et al.  Polymer Photovoltaic Cells: Enhanced Efficiencies via a Network of Internal Donor-Acceptor Heterojunctions , 1995, Science.