Preparation of PCDTBT nanofibers with a diameter of 20 nm and their application to air-processed organic solar cells.

A strategy for fabricating organic photovoltaic (OPV) devices based on PCDTBT nanofibers and PC70BM is described. Electrospinning techniques are used to prepare PCDTBT nanofibers and OPV devices in ambient air. The diameters of the PCDTBT nanofibers are approximately twice the exciton diffusion length, 20 nm. The active layer exhibits 100% photoluminescence quenching due to the small nanofiber diameter, indicating that the excitons are efficiently dissociated. The electrospun PCDTBT nanofibers absorb more photons at longer wavelengths, leading to improved photon harvesting. OPV devices composed of PCDTBT nanofibers show a high short circuit current of 11.54 mA cm(-2) and a high power conversion efficiency of 5.82%. The increase in the short circuit current is attributed to enhanced photon harvesting and charge transport. This method may be applied to the fabrication, in ambient air, of large-area active layers composed of other new conjugated polymers to yield high-performance OPV devices.

[1]  Yi Cui,et al.  Electrospun metal nanofiber webs as high-performance transparent electrode. , 2010, Nano letters.

[2]  Eunkyoung Kim,et al.  Fabrication of ordered bulk heterojunction organic photovoltaic cells using nanopatterning and electrohydrodynamic spray deposition methods. , 2012, Nanoscale.

[3]  Alan J. Heeger,et al.  Intensity dependence of current-voltage characteristics and recombination in high-efficiency solution-processed small-molecule solar cells. , 2013, ACS nano.

[4]  Sujuan Wu,et al.  Investigation of High-Performance Air-Processed Poly(3-hexylthiophene)/Methanofullerene Bulk-Heterojunction Solar Cells , 2010 .

[5]  Youngkyoo Kim,et al.  Temperature/time-dependent crystallization of polythiophene: fullerene bulk heterojunction films for polymer solar cells. , 2010, Nanoscale.

[6]  Tae-Woo Lee,et al.  Three‐Dimensional Bulk Heterojunction Morphology for Achieving High Internal Quantum Efficiency in Polymer Solar Cells , 2009 .

[7]  Wi Hyoung Lee,et al.  Polymer blends with semiconducting nanowires for organic electronics , 2012 .

[8]  Feng Liu,et al.  On the morphology of polymer‐based photovoltaics , 2012 .

[9]  Nelson E. Coates,et al.  Bulk heterojunction solar cells with internal quantum efficiency approaching 100 , 2009 .

[10]  C. Black,et al.  High‐Performance Air‐Processed Polymer–Fullerene Bulk Heterojunction Solar Cells , 2009 .

[11]  Walter Hu,et al.  Nanoimprinted polymer solar cell. , 2012, ACS nano.

[12]  Ye Tao,et al.  Morphology control in polycarbazole based bulk heterojunction solar cells and its impact on device performance , 2011 .

[13]  T. Salim,et al.  Carrier Dynamics in Polymer Nanofiber:Fullerene Solar Cells , 2012 .

[14]  Xiong Gong,et al.  Thermally Stable, Efficient Polymer Solar Cells with Nanoscale Control of the Interpenetrating Network Morphology , 2005 .

[15]  F. Krebs,et al.  Stability/degradation of polymer solar cells , 2008 .

[16]  Young Chul Kim,et al.  Highly aligned ultrahigh density arrays of conducting polymer nanorods using block copolymer templates. , 2008, Nano letters.

[17]  S. Ramakrishna,et al.  Novel hollow mesoporous 1D TiO2 nanofibers as photovoltaic and photocatalytic materials. , 2012, Nanoscale.

[18]  G. Lu,et al.  Self-assembled CdS/Au/ZnO heterostructure induced by surface polar charges for efficient photocatalytic hydrogen evolution , 2013 .

[19]  T. Russell,et al.  P3HT nanopillars for organic photovoltaic devices nanoimprinted by AAO templates. , 2012, ACS nano.

[20]  Seung Jae Yang,et al.  Preparation and photoluminescence (PL) performance of a nanoweb of P3HT nanofibers with diameters below 100 nm , 2011 .

[21]  Yuan Zhang,et al.  Effects of Impurities on Operational Mechanism of Organic Bulk Heterojunction Solar Cells , 2013, Advanced materials.

[22]  S. Darling,et al.  Morphology characterization in organic and hybrid solar cells , 2012 .

[23]  Klaus Meerholz,et al.  Morphology Control in Solution‐Processed Bulk‐Heterojunction Solar Cell Mixtures , 2009 .

[24]  Benjamin J. Schwartz,et al.  Reappraising the Need for Bulk Heterojunctions in Polymer−Fullerene Photovoltaics: The Role of Carrier Transport in All-Solution-Processed P3HT/PCBM Bilayer Solar Cells , 2009 .

[25]  Michael D. McGehee,et al.  Polymer-based solar cells , 2007 .

[26]  Andrea Bernardi,et al.  The role of buffer layers in polymer solar cells , 2011 .

[27]  Hee-Sang Shim,et al.  Efficient photovoltaic device fashioned of highly aligned multilayers of electrospun TiO2 nanowire array with conjugated polymer , 2008 .

[28]  A. Alivisatos,et al.  Hybrid Nanorod-Polymer Solar Cells , 2002, Science.

[29]  Tae Hoon Kim,et al.  Advanced energy storage device: a hybrid BatCap system consisting of battery–supercapacitor hybrid electrodes based on Li4Ti5O12–activated-carbon hybrid nanotubes , 2012 .

[30]  Younan Xia,et al.  Electrospun Nanofibers of Blends of Conjugated Polymers: Morphology, Optical Properties, and Field-Effect Transistors , 2005 .

[31]  Yeong Don Park,et al.  Solubility‐Induced Ordered Polythiophene Precursors for High‐Performance Organic Thin‐Film Transistors , 2009 .

[32]  Zhixiang Wei,et al.  Self-Assembly of Well-Defined Poly(3-hexylthiophene) Nanostructures toward the Structure–Property Relationship Determination of Polymer Solar Cells , 2012 .

[33]  Varun Vohra,et al.  Organic solar cells based on nanoporous P3HT obtained from self-assembled P3HT:PS templates , 2012 .

[34]  J. Jung,et al.  Annealing‐Free High Efficiency and Large Area Polymer Solar Cells Fabricated by a Roller Painting Process , 2010 .

[35]  Meng-Huan Jao,et al.  Additives for morphology control in high-efficiency organic solar cells , 2013 .

[36]  Jonathan M. Ziebarth,et al.  Enhanced Hole Mobility in Regioregular Polythiophene Infiltrated in Straight Nanopores , 2005 .

[37]  Valentin D. Mihailetchi,et al.  Charge Transport and Photocurrent Generation in Poly(3‐hexylthiophene): Methanofullerene Bulk‐Heterojunction Solar Cells , 2006 .

[38]  Seong‐Hyeon Hong,et al.  SnO2@TiO2 double-shell nanotubes for a lithium ion battery anode with excellent high rate cyclability. , 2013, Nanoscale.

[39]  N. S. Sariciftci,et al.  Conjugated polymer-based organic solar cells. , 2007, Chemical reviews.

[40]  Xiong Gong,et al.  New Architecture for High‐Efficiency Polymer Photovoltaic Cells Using Solution‐Based Titanium Oxide as an Optical Spacer , 2006 .

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

[42]  O Ok Park,et al.  Sequential processing: control of nanomorphology in bulk heterojunction solar cells. , 2011, Nano letters.

[43]  A. Steckl,et al.  Nanofiber‐Based Bulk‐Heterojunction Organic Solar Cells Using Coaxial Electrospinning , 2012 .

[44]  G. Choi,et al.  Percolation Behavior of Conductor-Insulator Composites with Varying Aspect Ratio of Conductive Fiber , 1999 .

[45]  Tao Wang,et al.  Correlating Structure with Function in Thermally Annealed PCDTBT:PC70BM Photovoltaic Blends , 2012 .

[46]  Stéphane Guillerez,et al.  Poly(3‐hexylthiophene) Fibers for Photovoltaic Applications , 2007 .

[47]  Changduk Yang,et al.  High-efficiency polymer solar cells with a cost-effective quinoxaline polymer through nanoscale morphology control induced by practical processing additives , 2013 .

[48]  Alan J. Heeger,et al.  Identifying a Threshold Impurity Level for Organic Solar Cells: Enhanced First‐Order Recombination Via Well‐Defined PC84BM Traps in Organic Bulk Heterojunction Solar Cells , 2011 .

[49]  S. Jenekhe,et al.  Nanowires of oligothiophene-functionalized naphthalene diimides: self assembly, morphology, and all-nanowire bulk heterojunction solar cells , 2012 .