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Toward a better understanding of conjugated polymer blends with non-spherical small molecules: coupling of molecular structure to polymer chain microstructure

Published online by Cambridge University Press:  05 January 2017

Michael Roders ,
Vincent V. Duong  and
Alexander L. Ayzner
Michael Roders
Affiliation:
Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
Vincent V. Duong
Affiliation:
Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
Alexander L. Ayzner*
Affiliation:
Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
*
a)Address all correspondence to this author. e-mail: aayzner@ucsc.edu
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Abstract

A major obstacle in the organic solar cell field is the inability to predict the relevant microstructural length scales that determine charge transport of the interpenetrating polymer/small molecule network based on the component chemical structures. This has led to a trial-and-error approach, which is extremely labor-intensive. This manuscript is our attempt to move toward forming a link between small molecule chemical structure and the morphological hierarchy of the blend. We focus on geometric motifs of small molecule organic semiconductors which have 2D, nonspherical 3D, and quasispherical 3D molecular orbital extent. We find that phase separation in these blends is a function of the molecular structure, and that the small molecule chemical structure is coupled to the crystallite orientation distribution of the polymer matrix. We further find that the ability of a molecule to form a network with a well-defined length scale of phase separation depends on the polymer persistence length.

Keywords

organicphotovoltaicmorphology
Type
Article
Information
Journal of Materials Research , Volume 32 , Issue 10: Focus Issue: Microstructural Characterization for Emerging Photovoltaic Materials , 26 May 2017 , pp. 1935 - 1945
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Copyright
Copyright © Materials Research Society 2017 

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Footnotes

Contributing Editor: Moritz Riede

References

REFERENCES

Sariciftci, N.S., Smilowitz, L., Braun, D., Srdanov, G., Srdanov, V., Wudl, F., and Heeger, A.J.: Observation of a photoinduced electron transfer from a conducting polymer (MEHPPV) onto C60 . Synth. Met. 56(2), 3125 (1993).Google Scholar
Yang, C.Y. and Heeger, A.J.: Morphology of composites of semiconducting polymers mixed with C60 . Synth. Met. 83(2), 85 (1996).Google Scholar
Dennler, G., Scharber, M.C., and Brabec, C.J.: Polymer-fullerene bulk-heterojunction solar cells. Adv. Mater. 21(13), 1323 (2009).Google Scholar
Huang, Y., Kramer, E.J., Heeger, A.J., and Bazan, G.C.: Bulk heterojunction solar cells: morphology and performance relationships. Chem. Rev. 114(14), 7006 (2014).Google Scholar
Park, S.H., Roy, A., Beaupre, S., Cho, S., Coates, N., Moon, J.S., Moses, D., Leclerc, M., Lee, K., and Heeger, A.J.: Bulk heterojunction solar cells with internal quantum efficiency approaching 100%. Nat. Photonics 3(5), 297 (2009).Google Scholar
Vandewal, K., Himmelberger, S., and Salleo, A.: Structural factors that affect the performance of organic bulk heterojunction solar cells. Macromolecules 46(16), 6379 (2013).CrossRefGoogle Scholar
Vandewal, K., Tvingstedt, K., and Inganäs, O.: Charge transfer states in organic donor–acceptor sol cells. Semicond. Semimetals 85, 261 (2011).CrossRefGoogle Scholar
Dimitrov, S.D. and Durrant, J.R.: Materials design considerations for charge generation in organic solar cells. Chem. Mater. 26(1), 616 (2014).Google Scholar
Rogers, J.T., Schmidt, K., Toney, M.F., Kramer, E.J., and Bazan, G.C.: Structural order in bulk heterojunction films prepared with solvent additives. Adv. Mater. 23(20), 2284 (2011).Google Scholar
Ayzner, A.L., Wanger, D.D., Tassone, C.J., Tolbert, S.H., and Schwartz, B.J.: Room to improve conjugated polymer-based solar cells: Understanding how thermal annealing affects the fullerene component of a bulk heterojunction photovoltaic device. J. Phys. Chem. C 112(48), 18711 (2008).Google Scholar
Verploegen, E., Mondal, R., Bettinger, C.J., Sok, S., Toney, M.F., and Bao, Z.: Effects of thermal annealing upon the morphology of polymer–fullerene blends. Adv. Funct. Mater. 20(20), 3519 (2010).Google Scholar
Zheng, L., Liu, J., Ding, Y., and Han, Y.: Morphology evolution and structural transformation of solution-processed methanofullerene thin film under thermal annealing. J. Phys. Chem. B 115(25), 8071 (2011).CrossRefGoogle ScholarPubMed
DeLongchamp, D.M., Kline, R.J., Fischer, D.A., Richter, L.J., and Toney, M.F.: Molecular characterization of organic electronic films. Adv. Mater. 23(3), 319 (2011).CrossRefGoogle ScholarPubMed
Kurrle, D. and Pflaum, J.: Exciton diffusion length in the organic semiconductor diindenoperylene. Appl. Phys. Lett. 92(13), 133306 (2008).CrossRefGoogle Scholar
Lin, J.D.A., Mikhnenko, O.V., Chen, J., Masri, Z., Ruseckas, A., Mikhailovsky, A., Raab, R.P., Liu, J., Blom, P.W.M., Loi, M.A., García-Cervera, C.J., Samuel, I.D.W., and Nguyen, T-Q.: Systematic study of exciton diffusion length in organic semiconductors by six experimental methods. Mater. Horiz. 1(2), 280 (2014).Google Scholar
Luhman, W.A. and Holmes, R.J.: Investigation of energy transfer in organic photovoltaic cells and impact on exciton diffusion length measurements. Adv. Funct. Mater. 21(4), 764 (2011).Google Scholar
Lunt, R.R., Benziger, J.B., and Forrest, S.R.: Relationship between crystalline order and exciton diffusion length in molecular organic semiconductors. Adv. Mater. 22(11), 1233 (2010).Google Scholar
Lunt, R.R., Giebink, N.C., Belak, A.A., Benziger, J.B., and Forrest, S.R.: Exciton diffusion lengths of organic semiconductor thin films measured by spectrally resolved photoluminescence quenching. J. Appl. Phys. 105(5), 053711 (2009).Google Scholar
Rim, S-B., Fink, R.F., Schöneboom, J.C., Erk, P., and Peumans, P.: Effect of molecular packing on the exciton diffusion length in organic solar cells. Appl. Phys. Lett. 91(17), 173504 (2007).CrossRefGoogle Scholar
You, J., Dou, L., Yoshimura, K., Kato, T., Ohya, K., Moriarty, T., Emery, K., Chen, C.C., Gao, J., Li, G., and Yang, Y.: A polymer tandem solar cell with 10.6% power conversion efficiency. Nat. Commun. 4, 1446 (2013).Google Scholar
Pandey, L., Risko, C., Norton, J.E., and Brédas, J-L.: Donor–acceptor copolymers of relevance for organic photovoltaics: A theoretical investigation of the impact of chemical structure modifications on the electronic and optical properties. Macromolecules 45(16), 6405 (2012).Google Scholar
Kim, D.H., Ayzner, A.L., Appleton, A.L., Schmidt, K., Mei, J., Toney, M.F., and Bao, Z.: Comparison of the photovoltaic characteristics and nanostructure of fullerenes blended with conjugated polymers with siloxane-terminated and branched aliphatic side chains. Chem. Mater. 25(3), 431 (2013).Google Scholar
Liu, T. and Troisi, A.: What makes fullerene acceptors special as electron acceptors in organic solar cells and how to replace them. Adv. Mater. 25(7), 1038 (2013).Google Scholar
Sauvé, G. and Fernando, R.: Beyond fullerenes: Designing alternative molecular electron acceptors for solution-processable bulk heterojunction organic photovoltaics. J. Phys. Chem. Lett. 6(18), 3770 (2015).Google Scholar
Orlandi, G. and Negri, F.: Electronic states and transitions in C60 and C70 fullerenes. Photochem. Photobiol. Sci. 1(5), 289 (2002).Google Scholar
Shivanna, R., Shoaee, S., Dimitrov, S., Kandappa, S.K., Rajaram, S., Durrant, J.R., and Narayan, K.S.: Charge generation and transport in efficient organic bulk heterojunction solar cells with a perylene acceptor. Energy Environ. Sci. 7(1), 435 (2014).Google Scholar
Beljonne, D., Cornil, J.r.m., Muccioli, L., Zannoni, C., Brédas, J-L., and Castet, F.d.r.: Electronic processes at organic–organic interfaces: Insight from modeling and implications for opto-electronic devices†. Chem. Mater. 23(3), 591 (2011).Google Scholar
Rand, B.P., Cheyns, D., Vasseur, K., Giebink, N.C., Mothy, S., Yi, Y., Coropceanu, V., Beljonne, D., Cornil, J., Brédas, J-L., and Genoe, J.: The impact of molecular orientation on the photovoltaic properties of a phthalocyanine/fullerene heterojunction. Adv. Funct. Mater. 22(14), 2987 (2012).Google Scholar
Ayzner, A.L., Nordlund, D., Kim, D-H., Bao, Z., and Toney, M.F.: Ultrafast electron transfer at organic semiconductor interfaces: Importance of molecular orientation. J. Phys. Chem. Lett. 6(1), 6 (2015).CrossRefGoogle ScholarPubMed
Wang, S., Fabiano, S., Himmelberger, S., Puzinas, S., Crispin, X., Salleo, A., and Berggren, M.: Experimental evidence that short-range intermolecular aggregation is sufficient for efficient charge transport in conjugated polymers. Proc. Natl. Acad. Sci. U. S. A. 112(34), 10599 (2015).Google Scholar
Als-Nielsen, J., Jacquemain, D., Kjaer, K., Leveiller, F., Lahav, M., and Leiserowitz, L.: Principles and applications of grazing incidence X-ray and neutron scattering from ordered molecular monolayers at the air–water interface. Phys. Rep. 246(5), 251 (1994).Google Scholar
Cruickshank, A.C., Dotzler, C.J., Din, S., Heutz, S., Toney, M.F., and Ryan, M.P.: The crystalline structure of copper phthalocyanine films on ZnO(1100). J. Am. Chem. Soc. 134(35), 14302 (2012).CrossRefGoogle ScholarPubMed
Fritz, S.E., Martin, S.M., Frisbie, C.D., Ward, M.D., and Toney, M.F.: Structural characterization of a pentacene monolayer on an amorphous SiO2 substrate with grazing incidence x-ray diffraction. J. Am. Chem. Soc. 126(13), 4084 (2004).Google Scholar
Ofuji, M., Inaba, K., Omote, K., Hoshi, H., Takanishi, Y., Ishikawa, K., and Takezoe, H.: Grazing incidence in-plane X-ray diffraction study on oriented copper phthalocyanine thin films. Jpn. J. Appl. Phys., Part 1 41(8), 5467 (2002).CrossRefGoogle Scholar
Vineyard, G.H.: Grazing-incidence diffraction and the distorted-wave approximation for the study of surfaces. Phys. Rev. B: Condens. Matter Mater. Phys. 26(8), 4146 (1982).Google Scholar
Treat, N.D., Brady, M.A., Smith, G., Toney, M.F., Kramer, E.J., Hawker, C.J., and Chabinyc, M.L.: Interdiffusion of PCBM and P3HT reveals miscibility in a photovoltaically active blend. Adv. Energy Mater. 1(1), 82 (2011).Google Scholar
Gargi, D., Kline, R.J., DeLongchamp, D.M., Fischer, D.A., Toney, M.F., and O’Connor, B.T.: Charge transport in highly face-on poly(3-hexylthiophene) films. J. Phys. Chem. C 117(34), 17421 (2013).Google Scholar
O’Connor, B., Kline, R.J., Conrad, B.R., Richter, L.J., Gundlach, D., Toney, M.F., and DeLongchamp, D.M.: Anisotropic structure and charge transport in highly strain-aligned regioregular poly(3-hexylthiophene). Adv. Funct. Mater. 21(19), 3697 (2011).Google Scholar
Baker, J.L., Jimison, L.H., Mannsfeld, S., Volkman, S., Yin, S., Subramanian, V., Salleo, A., Alivisatos, A.P., and Toney, M.F.: Quantification of thin film crystallographic orientation using x-ray diffraction with an area detector. Langmuir 26(11), 9146 (2010).Google Scholar
Guo, S., Ruderer, M.A., Rawolle, M., Korstgens, V., Birkenstock, C., Perlich, J., and Muller-Buschbaum, P.: Evolution of lateral structures during the functional stack build-up of P3HT:PCBM-based bulk heterojunction solar cells. ACS Appl. Mater. Interfaces 5(17), 8581 (2013).Google Scholar
Rauscher, M., Salditt, T., and Spohn, H.: Small-angle X-ray scattering under grazing incidence: The cross section in the distorted-wave Born approximation. Phys. Rev. B: Condens. Matter Mater. Phys. 52(23), 16855 (1995).Google Scholar
Renaud, G., Lazzari, R., and Leroy, F.: Probing surface and interface morphology with grazing incidence small angle X-ray scattering. Surf. Sci. Rep. 64(8), 255 (2009).Google Scholar
Ungar, G., Liu, F., Zeng, X.B., Glettner, B., Prehm, M., Kieffer, R., and Tschierske, C.: GISAXS in the study of supramolecular and hybrid liquid crystals. J. Phys.: Conf. Ser. 247, 012032 (2010).Google Scholar
Dante, M., Peet, J., and Nguyen, T-Q.: Nanoscale charge transport and internal structure of bulk heterojunction conjugated polymer/fullerene solar cells by scanning probe microscopy. J. Phys. Chem. C 112(18), 7241 (2008).Google Scholar
Tassone, C.J., Ayzner, A.L., Kennedy, R.D., Halim, M., So, M., Rubin, Y., Tolbert, S.H., and Schwartz, B.J.: Using pentaarylfullerenes to understand network formation in conjugated polymer-based bulk-heterojunction solar cells. J. Phys. Chem. C 115(45), 22563 (2011).Google Scholar
Ayzner, A.L., Tassone, C.J., Tolbert, S.H., and Schwartz, B.J.: Reappraising the need for bulk heterojunctions in polymer–fullerene photovoltaics: The role of carrier transport in all-solution-processed P3HT/PCBM bilayer solar cells. J. Phys. Chem. C 113(46), 20050 (2009).Google Scholar
Guinier, A.: X-ray Diffraction: In Crystals, Imperfect Crystals, and Amorphous Bodies (Dover Publications, Mineola, 2013).Google Scholar
Weyerich, B., Brunner-Popela, J., and Glatter, O.: Small-angle scattering of interacting particles. II. Generalized indirect Fourier transformation under consideration of the effective structure factor for polydisperse systems. J. Appl. Crystallogr. 32(2), 197 (1999).Google Scholar
Kim, Y., Choulis, S.A., Nelson, J., Bradley, D.D.C., Cook, S., and Durrant, J.R.: Composition and annealing effects in polythiophene/fullerene solar cells. J. Mater. Sci. 40(6), 1371 (2005).Google Scholar
Hoppe, H. and Sariciftci, N.S.: Morphology of polymer/fullerene bulk heterojunction solar cells. J. Mater. Chem. 16(1), 45 (2006).CrossRefGoogle Scholar
Shrotriya, V., Li, G., Yao, Y., Moriarty, T., Emery, K., and Yang, Y.: Accurate measurement and characterization of organic solar cells. Adv. Funct. Mater. 16(15), 2016 (2006).Google Scholar
Fink, J., Schierle, E., Weschke, E., and Geck, J.: Resonant elastic soft X-ray scattering. Rep. Prog. Phys. 76(5), 056502 (2013).Google Scholar
Grenier, S. and Joly, Y.: Basics of resonant elastic X-ray scattering theory. J. Phys.: Conf. Ser. 519, 012001 (2014).Google Scholar
Vettier, C.: Resonant elastic X-ray scattering: Where from? Where to?. Eur. Phys. J.: Spec. Top. 208(1), 3 (2012).Google Scholar
Liu, F., Brady, M.A., and Wang, C.: Resonant soft X-ray scattering for polymer materials. Eur. Polym. J. 81, 555 (2016).Google Scholar
Wang, C., Lee, D.H., Hexemer, A., Kim, M.I., Zhao, W., Hasegawa, H., Ade, H., and Russell, T.P.: Defining the nanostructured morphology of triblock copolymers using resonant soft X-ray scattering. Nano Lett. 11(9), 3906 (2011).Google Scholar
Araki, T., Ade, H., Stubbs, J.M., Sundberg, D.C., Mitchell, G.E., Kortright, J.B., and Kilcoyne, A.L.D.: Resonant soft X-ray scattering from structured polymer nanoparticles. Appl. Phys. Lett. 89(12), 124106 (2006).Google Scholar
Collins, B.A., Cochran, J.E., Yan, H., Gann, E., Hub, C., Fink, R., Wang, C., Schuettfort, T., McNeill, C.R., Chabinyc, M.L., and Ade, H.: Polarized X-ray scattering reveals non-crystalline orientational ordering in organic films. Nat. Mater. 11(6), 536 (2012).Google Scholar
Rivnay, J., Toney, M.F., Zheng, Y., Kauvar, I.V., Chen, Z., Wagner, V., Facchetti, A., and Salleo, A.: Unconventional face-on texture and exceptional in-plane order of a high mobility n-type polymer. Adv. Mater. 22(39), 4359 (2010).Google Scholar
Ayzner, A.L., Doan, S.C., Tremolet de Villers, B., and Schwartz, B.J.: Ultrafast studies of exciton migration and polaron formation in sequentially solution-processed conjugated polymer/fullerene quasi-bilayer photovoltaics. J. Phys. Chem. Lett. 3(16), 2281 (2012).Google Scholar
Ro, H.W., Akgun, B., O’Connor, B.T., Hammond, M., Kline, R.J., Snyder, C.R., Satija, S.K., Ayzner, A.L., Toney, M.F., Soles, C.L., and DeLongchamp, D.M.: Poly(3-hexylthiophene) and [6,6]-phenyl-C61-butyric acid methyl ester mixing in organic solar cells. Macromolecules 45(16), 6587 (2012).CrossRefGoogle Scholar
Chen, D., Liu, F., Wang, C., Nakahara, A., and Russell, T.P.: Bulk heterojunction photovoltaic active layers via bilayer interdiffusion. Nano Lett. 11(5), 2071 (2011).Google Scholar
Yan, Q., Zhou, Y., Zheng, Y-Q., Pei, J., and Zhao, D.: Towards rational design of organic electron acceptors for photovoltaics: A study based on perylenediimide derivatives. Chem. Sci. 4(12), 4389 (2013).Google Scholar
Sharenko, A., Proctor, C.M., van der Poll, T.S., Henson, Z.B., Nguyen, T-Q., and Bazan, G.C.: A high-performing solution-processed small molecule:perylene diimide bulk heterojunction solar cell. Adv. Mater. 25(32), 4403 (2013).Google Scholar
Kamm, V., Battagliarin, G., Howard, I.A., Pisula, W., Mavrinskiy, A., Li, C., Müllen, K., and Laquai, F.: Polythiophene:perylene diimide solar cells—The impact of alkyl-substitution on the photovoltaic performance. Adv. Energy Mater. 1(2), 297 (2011).CrossRefGoogle Scholar
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