Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-28T05:30:49.410Z Has data issue: false hasContentIssue false

Variable band gap conjugated polymers for optoelectronic and redox applications

Published online by Cambridge University Press:  01 December 2005

Young-Gi Kim
Affiliation:
The George and Josephine Butler Polymer Research Laboratories, Department of Chemistry, Center for Macromolecular Science and Engineering, University of Florida, Gainesville, Florida 32611
Barry C. Thompson
Affiliation:
The George and Josephine Butler Polymer Research Laboratories, Department of Chemistry, Center for Macromolecular Science and Engineering, University of Florida, Gainesville, Florida 32611
Nisha Ananthakrishnan
Affiliation:
The George and Josephine Butler Polymer Research Laboratories, Department of Chemistry, Center for Macromolecular Science and Engineering, University of Florida, Gainesville, Florida 32611
G. Padmanaban
Affiliation:
The George and Josephine Butler Polymer Research Laboratories, Department of Chemistry, Center for Macromolecular Science and Engineering, University of Florida, Gainesville, Florida 32611
S. Ramakrishnan
Affiliation:
Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012 India
John R. Reynolds*
Affiliation:
The George and Josephine Butler Polymer Research Laboratories, Department of Chemistry, Center for Macromolecular Science and Engineering, University of Florida, Gainesville, Florida 32611
*
a) Address all correspondence to this author. e-mail: reynolds@chem.ufl.edu
Get access

Abstract

We report here on the utilization of variable band gap conjugated polymers for optoelectronic redox applications comprising organic photovoltaics, color tunable light emitting diodes, and electrochromics. For the evaluation of morphology in photovoltaicdevices, atomic force microscopy, and optical microscopy provided direct visualization of the blend film structure. The evolution of the morphology in two and three component blends incorporating poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenlenevinylene] (MEH-PPV), poly(methylmethacrylate) (PMMA), and [6, 6]-phenyl C61-butyric acid methyl ester (PCBM) was investigated. It was found that while insulating PMMA can be used to modulate the phase separation in these blends, a bicontinuous network of donor and acceptor was required to achieve the best device results. Similarily, a MEH-PPVcopolymer with a decreased conjugation length has been used for investigating inter- and intramolecular photoinduced charge transfer in the presence of PMMA and PCBM.We fabricated MEH-PPV/PCBM solar cells that have power conversion efficiencies up to 1.5% with a range of 0.7–1.5%, dependent on the nature of the MEH-PPV used. This further indicates that in addition to blend morphology, polymer structure is critical for optimizing device performance. To this end, the concept of an ideal donor for photovoltaic devices based on poly[2,5-di(3,7-dialkoxy)-cyanoterephthalylidene] is described and two donor-acceptor polymers based on cyanovinylene (CNV) and dioxythiophene are discussed as representative examples of soluble narrow band gap polymers synthesized in our group. For light emitting applications, utilization of two blue emitting conjugated polymers poly (9,9-dioctylfluorene) (PFO) and poly[(9,9-dihexylfluorenyl-2,7-diyl)-co-(9,ethyl-3,6-carbazole)] (PFH-PEtCz)is presented for a color tunable polymer light emitting diode that emits orange, green, and blue light with a voltage range of 7–10 V as a function of the total conjugated polymer content in PMMA and is attributed to the phase separation between the conjugated polymers. Finally, the narrow band gap conjugated polymer, poly[bis(3,4-propylenedioxythiophene-dihexyl)]-cyanovinylene has been characterized for its electrochromic properties, illustrating the multifunctional nature of variable band gap conjugated polymers.

Type
Articles—Energy and The Environment Special Section
Copyright
Copyright © Materials Research Society 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Peumans, P., Uchida, S. and Forrest, S.R.: Efficient bulk heterojunction photovoltaic cells using small-molecular-weight organic thin films. Nature 425, 158 (2003).CrossRefGoogle ScholarPubMed
2.Shaheen, S.E., Brabec, C.J., Sariciftci, N.S., Padinger, F., Fromherz, T. and Hummelen, J.C.: 2.5% efficient organic plastic solar cells. Appl. Phys. Lett. 78, 841 (2001).CrossRefGoogle Scholar
3.Zhang, F.L., Johansson, M., Andersson, M.R., Hummelen, J.C. and Inganas, O.: Polymer solar cells based on MEH-PPV and PCBM. Synth. Met. 137, 1401 (2003).CrossRefGoogle Scholar
4.Inganas, O., Roman, L.S., Zhang, F., Johansson, D.M., Andersson, M.R. and Hummelen, J.C.: Recent progress in thin film organic photodiodes. Synth. Met. 121, 1525 (2001).CrossRefGoogle Scholar
5.Brabec, C.J., Sariciftci, N.S. and Hummelen, J.C.: Plastic solar cells. Adv. Funct. Mater. 11, 15 (2001).3.0.CO;2-A>CrossRefGoogle Scholar
6.Dhanabalan, A., Van Duren, J.K.J., Van Hal, P.A., Van Dongen, J.L.J. and Janssen, R.A.J.: Synthesis and characterization of a low bandgap conjugated polymer for bulk heterojunction photovoltaic cells. Adv. Funct. Mater. 11, 255 (2001).3.0.CO;2-I>CrossRefGoogle Scholar
7.Camaioni, N., Garlaschelli, L., Geri, A., Maggini, M., Possamai, G. and Ridolfi, G.: Solar cells based on poly(3-alkyl)thiophenes and [60]fullerene: A comparative study. J. Mater. Chem. 12, 2065 (2002).CrossRefGoogle Scholar
8.Rispens, M.T., Meetsma, A., Rittberger, R., Brabec, C.J., Sariciftci, N.S., and Hummelen, J.C.: Influence of the solvent on the crystal structure of PCBM and the efficiency of MDMO-PPV: PCBM plastic solar cells. Chem. Commun. 2116 (2003).Google Scholar
9.Alem, S., de Bettignies, R., Nunzi, J-M. and Cariou, M.: Efficient polymer-based interpenetrated network photovoltaic cells. Appl. Phys. Lett. 84, 2178 (2004).CrossRefGoogle Scholar
10.Padinger, F., Rittberger, R.S. and Sariciftci, N.S.: Effects of postproduction treatment on plastic solar cells. Adv. Funct. Mater. 13, 85 (2003).CrossRefGoogle Scholar
11.Vangeneugden, D.L., Vanderzande, D.J.M., Salbeck, J., van Hal, P.A., Janssen, R.A.J., Hummelen, J.C., Brabec, C.J., Shaheen, S.E. and Sariciftci, N.S.: Synthesis and characterization of a poly(1,3-dithienylisothianaphthene) derivative for bulk heterojunction photovoltaic cells. J. Phys. Chem. B 105, 11106 (2001).CrossRefGoogle Scholar
12.Stubinger, T. and Brutting, W.: Exciton diffusion and optical interference in organic donor-acceptor photovoltaic cells. J. Appl. Phys. 90, 3632 (2001).CrossRefGoogle Scholar
13.Gadisa, A., Svensson, M., Andersson, M.R. and Inganas, O.: Correlation between oxidation potential and open-circuit voltage of composite solar cells based on blends of polythiophenes/ fullerene derivative. Appl. Phys. Lett. 84, 1609 (2004).CrossRefGoogle Scholar
14.Zhou, Q., Hou, Q., Zheng, L., Deng, X., Yu, G. and Cao, Y.: Fluorenebased low band-gap copolymers for high performance photovoltaic devices. Appl. Phys. Lett. 84, 1653 (2004).CrossRefGoogle Scholar
15.Brabec, C.J., Cravino, A., Meissner, D., Sariciftci, N.S., Fromherz, T., Rispens, M.T., Sanchez, L. and Hummelen, J.C.: Origin of the open circuit voltage of plastic solar cells. Adv. Funct. Mater. 11, 374 (2001).3.0.CO;2-W>CrossRefGoogle Scholar
16.Chirvase, D., Chiguvare, Z., Knipper, M., Parisi, J., Dyakonov, V. and Hummelen, J.C.: Electrical and optical design and characterization of regioregular poly(3-hexylthiophene-2,5-diyl)/fullerene-based heterojunction polymer solar cells. Synth. Met. 138, 299 (2003).CrossRefGoogle Scholar
17.Nogueira, A.F., Montanari, I., Nelson, J., Durrant, J.R., Winder, C., Sariciftci, N.S. and Brabec, C.: Charge recombination in conjugated polymer/fullerene blended films studied by transient absorption spectroscopy. J. Phys. Chem. B 107, 1567 (2003).CrossRefGoogle Scholar
18.Garnier, F.: Organic-based electronics a la carte. Acc. Chem. Res. 32, 209 (1999).CrossRefGoogle Scholar
19.Moons, E.: Conjugated polymer blends: Linking film morphology to performance of light emitting diodes and photodiodes. J. Phys.: Condens. Matter 14, 12235 (2002).Google Scholar
20.Van Hutten, P.F. and Hadziioannou, G.: The role of interfaces in photovoltaic devices. Monatsh. Chem. 132, 129 (2001).CrossRefGoogle Scholar
21.Liu, J., Shi, Y. and Yang, Y.: Solvation-induced morphology effects on the performance of polymer-based photovoltaic devices. Adv. Funct. Mater. 11, 420 (2001).3.0.CO;2-K>CrossRefGoogle Scholar
22.Gebeyehu, D., Brabec, C.J., Padinger, F., Fromherz, T., Hummelen, J.C., Badt, D., Schindler, H. and Sariciftci, N.S.: The interplay of efficiency and morphology in photovoltaic devices based on interpenetrating networks of conjugated polymers with fullerenes. Synth. Met. 118, 1 (2001).CrossRefGoogle Scholar
23.Martens, T., D’Haen, J., Munters, T., Beelen, Z., Goris, L., Manca, J., D’Olieslaeger, M., Vanderzande, D., De Schepper, L. and Andriessen, R.: Disclosure of the nanostructure of MDMO-PPV:PCBM bulk hetero-junction organic solar cells by a combination of SPM and TEM. Synth. Met. 138, 243 (2003).CrossRefGoogle Scholar
24.Yang, X., Van Duren, J.K.J., Janssen, R.A.J., Michels, M.A.J. and Loos, J.: Morphology and thermal stability of the active layer in poly(p-phenylenevinylene)/methanofullerene plastic photovoltaic devices. Macromol. 37, 2151 (2004).CrossRefGoogle Scholar
25.Wienk, M.M., Kroon, J.M., Verhees, W.J.H., Knol, J., Hummelen, J.C., van Hal, P.A. and Janssen, R.A.J.: Efficient methano[70]fullerene/MDMO-PPV bulk heterojunction photovoltaic cells. Angew. Chem. Int. Ed. 42, 3371 (2003).CrossRefGoogle Scholar
26.Brabec, C.J., Padinger, F., Sariciftci, N.S. and Hummelen, J.C.: Photovoltaic properties of conjugated polymer/methanofullerene composites embedded in a polystyrene matrix. J. Appl. Phys. 85, 6866 (1999).CrossRefGoogle Scholar
27.Braun, D. and Heeger, A.J.: Visible light emission from semiconducting polymer diodes. Appl. Phys. Lett. 58, 1982 (1991).CrossRefGoogle Scholar
28.Burroughes, J.H., Bradley, D.D.C., Brown, A.R., Marks, R.N., Mackay, K., Friend, R.H., Burns, P.L. and Holmes, A.B.: Light-emitting diodes based on conjugated polymers. Nature 347, 539 (1990).CrossRefGoogle Scholar
29.Kraft, A., Grimsdale, A.C. and Holmes, A.B.: Electroluminescent conjugated polymers-seeing polymers in a new light. Angew. Chem. Int. Ed. 37, 403 (1998).3.0.CO;2-9>CrossRefGoogle Scholar
30.Wang, Y.Z., Sun, R.G., Meghdadi, F., Leising, G. and Epstein, A.J.: Multicolor multilayer light-emitting devices based on pyridine-containing conjugated polymers and para-sexiphenyl oligomer. Appl. Phys. Lett. 74, 3613 (1999).CrossRefGoogle Scholar
31.Huang, C.C., Meng, H.F., Ho, G.K., Chen, C.H., Hsu, C.S., Huang, J.H., Horng, S.F., Chen, B.X. and Chen, L.C.: Color-tunable multilayer light-emitting diodes based on conjugated polymers. Appl. Phys. Lett. 84, 1195 (2004).CrossRefGoogle Scholar
32.Gowri, R., Mandal, D., Shivkumar, B. and Ramakrishnan, S.: Synthesis of novel poly[(2,5-dimethoxy-p-phenylene)vinylene] precursors having two eliminatable groups: An approach for the control of conjugation length. Macromol. 31, 1819 (1998).CrossRefGoogle Scholar
33.Jin, S-H., Kang, S-Y., Yeom, I-S., Kim, J.Y., Park, S.H., Lee, K., Gal, Y-S. and Cho, H-N.: Color-tunable electroluminescent polymers by substituents on the poly(p-phenylenevinylene) derivatives for light-emitting diodes. Chem. Mater. 14, 5090 (2002).CrossRefGoogle Scholar
34.McGehee, M.D., Bergstedt, T., Zhang, C., Saab, A.P., O’Regan, M.B., Bazan, G.C., Srdanov, V.I. and Heeger, A.J.: Narrow bandwidth luminescence from blends with energy transfer from semiconducting conjugated polymers to europium complexes. Adv. Mater. 11, 1349 (1999).3.0.CO;2-W>CrossRefGoogle Scholar
35.Romero, D.B., Schaer, M., Zuppiroli, L., Cesar, B. and Francois, B.: Effects of doping in polymer light-emitting diodes. Appl. Phys. Lett. 67, 1659 (1995).CrossRefGoogle Scholar
36.Ding, L., Karasz, F.E., Lin, Z., Zheng, M., Liao, L. and Pang, Y.: Effect of Foerster energy transfer and hole transport layer on performance of polymer light-emitting diodes. Macromol. 34, 9183 (2001).CrossRefGoogle Scholar
37.Morgado, J., Moons, E., Friend, R.H. and Cacialli, F.: Optical and morphological investigations of non-homogeneity in polyfluorene blends. Synth. Met. 124, 63 (2001).CrossRefGoogle Scholar
38.Alam, M.M., Tonzola, C.J. and Jenekhe, S.A.: Nanophase-separated blends of acceptor and donor conjugated polymers. Efficient electroluminescence from binary polyquinoline/poly (2-methoxy-5-(2′-ethylhexyl-oxy)-1,4-phenylenevinylene) and polyquinoline/poly(3-octyl thiophene) blends. Macromol. 36, 6577 (2003).CrossRefGoogle Scholar
39.Berggren, M., Inganas, O., Gustafsson, G., Rasmusson, J., Andersson, M.R., Hjertberg, T. and Wennerstrom, O.: Light-emitting diodes with variable colors from polymer blends. Nature 372, 444 (1994).CrossRefGoogle Scholar
40.Monk, P.S.M., Mortimer, R.J. and Rosseinsky, D.R.: Electrochromism: Principles and Applications (VCH, Weinheim, Germany, 1995).CrossRefGoogle Scholar
41.Argun, A.A., Aubert, P-H., Thompson, B.C., Schwendeman, I., Gaupp, C.L., Hwang, J., Pinto, N.J., Tanner, D.B., MacDiarmid, A.G. and Reynolds, J.R.: Multicolored electrochromism in polymers: Structures and devices. Chem. Mater. 16, 4401 (2004).CrossRefGoogle Scholar
42.Thomas, C.A., Zong, K., Abboud, K.A., Steel, P.J. and Reynolds, J.R.: Donor-mediated band gap reduction in a homologous series of conjugated polymers. J. Am. Chem. Soc. 126, 16440 (2004).CrossRefGoogle Scholar
43.Soenmez, G., Schwendeman, I., Schottland, P., Zong, K. and Reynolds, J.R.: N-substituted poly(3,4-propylenedioxypyrrole)s: High gap and low redox potential switching electroactive and electrochromic polymers. Macromol. 36, 639 (2003).CrossRefGoogle Scholar
44.DuBois, C.J., Abboud, K.A. and Reynolds, J.R.: Electrolyte-controlled redox conductivity and n-type doping in poly(bis-EDOT-pyridine)s. J. Phys. Chem. B 108, 8550 (2004).CrossRefGoogle Scholar
45.Schwendeman, I., Hwang, J., Welsh, D.M., Tanner, D.B. and Reynolds, J.R.: Combined visible and infrared electrochromism using dual polymer devices. Adv. Mater. 13, 634 (2001).3.0.CO;2-3>CrossRefGoogle Scholar
46.Schwendeman, I., Hickman, R., Soenmez, G., Schottland, P., Zong, K., Welsh, D.M. and Reynolds, J.R.: Enhanced contrast dual polymer electrochromic devices. Chem. Mater. 14, 3118 (2002).CrossRefGoogle Scholar
47.Van Duren, J.K.J., Yang, X., Loos, J., Bulle-Lieuwma, C.W.T., Sieval, A.B., Hummelen, J.C. and Janssen, R.A.J.: Relating the morphology of poly(p-phenylene vinylene)/methanofullerene blends to solar cell performance. Adv. Funct. Mater. 14, 425 (2004).CrossRefGoogle Scholar
48.Zheng, L., Zhou, Q., Deng, X., Yuan, M., Yu, G. and Cao, Y.: Methanofullerenes used as electron acceptors in polymer photovoltaic devices. J. Phys. Chem. B 108, 11921 (2004).CrossRefGoogle Scholar
49.Padmanaban, G. and Ramakrishnan, S.: Conjugation length control in soluble poly[2-methoxy-5-((2′-ethylhexyl)oxy)-1,4-phenylenevinylene] (MEHPPV): Synthesis, optical properties, and energy transfer. J. Am. Chem. Soc. 122, 2244 (2000).CrossRefGoogle Scholar
50.Roncali, J.: Synthetic principles for bandgap control in linear p-conjugated systems. Chem. Rev. 97, 173 (1997).CrossRefGoogle Scholar
51.van Mullekom, H.A.M., Vekemans, J.A.J.M., Havinga, E.E. and Meijer, E.W.: Developments in the chemistry and band gap engineering of donor-acceptor substituted conjugated polymers. Mater. Sci. Eng. R: Reports R32, 1 (2001).CrossRefGoogle Scholar
52.Winder, C. and Sariciftci, N.S.: Low bandgap polymers for photon harvesting in bulk heterojunction solar cells. J. Mater. Chem. 14, 1077 (2004).CrossRefGoogle Scholar
53.Meskers, S.C.J., Huebner, J., Oestreich, M. and Baessler, H.: Dispersive relaxation dynamics of photoexcitations in a polyfluorene film involving energy transfer: Experiment and Monte Carlo simulations. J. Phys. Chem. B 105, 9139 (2001).CrossRefGoogle Scholar
54.de Leeuw, D.M., Simenon, M.M.J., Brown, A.R. and Einerhand, R.E.F.: Stability of n -type doped conducting polymers and consequences for polymeric microelectronic devices. Synth. Met. 87, 53 (1997).CrossRefGoogle Scholar
55.Li, Y., Cao, Y., Gao, J., Wang, D., Yu, G. and Heeger, A.J.: Electrochemical properties of luminescent polymers and polymer light-emitting electrochemical cells. Synth. Met. 99, 243 (1999).CrossRefGoogle Scholar
56.Bard, A.J. and Faulkner, L.R.: Electrochemical methods: Fundamentals and applications. Dianhuaxue 7, 255 (2001).Google Scholar
57.Pavlishchuk, V.V., Addison, A.W.: Conversion constants for redox potentials measured versus different reference electrodes in acetonitrile solutions at 25 °C. Inorg. Chim. Acta 298, 97 (2000).CrossRefGoogle Scholar
58.Iyengar, N.A., Harrison, B., Duran, R.S., Schanze, K.S. and Reynolds, J.R.: Morphology evolution in nanoscale light-emitting domains in MEH-PPV/PMMA blends. Macromolecules 36, 8978 (2003).CrossRefGoogle Scholar
59.Fusalba, F., Ho, H.A., Breau, L. and Belanger, D.: Poly(cyano-substituted diheteroareneethylene) as active electrode material for electrochemical supercapacitors. Chem. Mater. 12, 2581 (2000).CrossRefGoogle Scholar
60.Ghosh, S. and Inganas, O.: Conducting polymer hydrogels as 3D electrodes. Applications for supercapacitors. Adv. Mater. 11, 1214 (1999).3.0.CO;2-3>CrossRefGoogle Scholar