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Polymer Solar Cells Employing Water-Soluble Polypyrrole Nanoparticles as Dopants of PEDOT:PSS with Enhanced Efficiency and Stability Xingye Zhang, Bin Zhang, Xinhua Ouyang, Lihui Chen, and Hui Wu J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.7b05767 • Publication Date (Web): 14 Aug 2017 Downloaded from http://pubs.acs.org on August 14, 2017

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The Journal of Physical Chemistry

Polymer Solar Cells Employing Water-Soluble Polypyrrole Nanoparticles as Dopants of PEDOT:PSS with Enhanced Efficiency and Stability

Xingye Zhang,a,c# Bin Zhang,a,b#, Xinhua Ouyanga*, Lihui Chen,a Hui Wu*a a

College of Materials Science and Engineering, Fujian Agriculture and Forest

University, Fuzhou, Fujian, P. R. China b

Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of

Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China c

College of Information Science & Electronic Engineering, Zhejiang University,

Hangzhou, Zhejiang, P. R. China # These authors contributed equally to this work Corresponding author: [email protected] (X. Ouyang); [email protected] (H. Wu)

Abstract: Water-soluble polypyrrole nanoparticles (PPy NPs) were developed and demonstrated as effective modifiers of PEDOT:PSS. By using them as the anode interfaces of polymer solar cells (PSCs), these PSCs showed a high power conversion efficiency (PCE) with the value of 9.48% as doping 20% PPy NPs into PEDOT:PSS. Interestingly, the enhancement of ~16% and ~150% compared with that of pure PEDOT:PSS (PCE=8.04%) and PEDOT:PSS-free (PCE= 3.76%) was observed. Importantly, the stability of these devices with 20% PPy NPs doped PEDOT:PSS was also improved significantly. The enhanced performance was possible attributed to the changes of pH value, enhanced conductivities, and morphological changes of PEDOT:PSS. Our study supplies an alternative method to obtain high-efficient PSCs with the development of polymer NPs interfacial materials.

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Introduction In the past two decades, interfacial modification of electrodes for polymer solar cells (PSCs) has been attracting extensive interest owing to its important role in promoting the performance of devices.1-3 A significant advancement has been made by developing novel interfacial materials to regulate carrier extraction behaviour of electrodes, and power conversion efficiencies (PCEs) of state-of-the-art PSCs over 10% have been achieved by using polymer and small-molecular interlayers as cathode modification, including conjugated polyfluorene derivatives (PFN)4, non-conjugated

polyethyleneimine

(PEIE)5,

non-conjugated

small-molecule

electrolyte (MSAPBS)6. However, the studies on anode modification are relatively lagged behind its counterparts of cathode interfaces. In this regard, it is highly desirable to explore novel materials with superior interfacial properties for the anode of PSCs. Generally, an anode interface with excellent performance should satisfy several key factors such as orthogonality with the processing solvent of active layer, high transparency, and suitable HOMO level. To date, semiconducting metal oxides7, polymers and their composites8, small-molecule organic materials9, self-assembled monolayers10 and graphene oxides11 have been demonstrated for effective anode interfaces to modify PSCs. As a representative conducting polymer, poly(3,4-ethylene dioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) has been widely used as anode modified layers in PSCs due to its high conductivity, easy solution-processing and high work function (~5.2 eV).12 However, the pristine PEDOT:PSS film usually exhibits low conductivity ( 90%) was purchased from Nippon Sheet Glass Company, Ltd, and cleaned by sonication in detergent, deionized water, acetone, and isopropyl alcohol and dried in a nitrogen stream, followed by an UV-ozone treatment of 20 minutes. A 35-nm-thick PEDOT: PSS (Baytron P VP Al 4083, J&K Co.) or 20% PPy NPs doped PEDOT:PSS anode buffer layer was spin-casted on the ITO substrate and was heated on a hot plate at 140 oC for 20 min. The PTB7/P3HT, PC71BM/ PC61BM and DIO were purchased from 1-Material, American Dye Source, Inc. and Acros, respectively, and used as received. The PTB7 were blended with PC71BM and dissolved in chlorobenzene (CB) with the addition of a small amount of DIO (CB: DIO = 97:3, v/v). The blended ratios of polymer: PC71BM was 1:1.5 by weight, the solution was stirred overnight at 70 oC. Then the active layer were spin-coated at 2000 rpm for 120 s with a thickness of 90-110nm. In the end, 20 nm and 120 nm of Al were deposited through two shadow masks (defined active area: 0.09 cm2) onto the photoactive layer by thermoevaporation in a vacuum chamber with base pressure of 2×10-6mbar. All device fabrication processes are carried out in a N2-filled glovebox. J-V characterization and EQE measurement The current-voltage (J-V) characteristics of the unencapsulated PSCs were measured in a N2-filled glovebox using a Keithley 2450 source-measure unit and an AM 1.5 G solar simulator (Newport-Oriel® Sol3A 450W). The illumination intensity of 100 mW cm-2 irradiation was calibrated using a standard monocrystal Si reference cell (PV measurements Inc.) to ensure the accurate light source intensity. The external quantum efficiency (EQE) was conducted using the measurement system (Newport-Oriel® IQE 200TM).Same data acquisition system was used for the external quantum efficiency measurement. Under full computer 10


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control, light from a 150 W xenon lamp (Oriel, U.S.A.) was focused through a monochromator onto the PSC under testing. The wavelength of the light from the monochromator was increased progressively in the visible region to generate the EQE (λ) as defined by EQE (λ) = 12400(Jsc/λφ), where λ is the wavelength, Jsc is short-circuit photocurrent density (mA cm-2), and φ is the incident radiative flux (mW cm-2). EQE of the unencapsulated PSCs were measured in air.

Associated Content Supporting Information is available free of charge on the ACS Publications website. Photographs of color changes, Dark J-V characteristics, Elemental composition (PDF)

Acknowledgements This work was financially supported from the National Natural Science Foundation of China (21674123). H. Wu thanks the Award Program for Minjiang Scholar Professorship. ORCID Xinhua Ouyang: 0000-0003-2911-8283 ORCID Hui Wu: 0000-0002-9755-8371

References (1) Yin, Z. G.; Wei, J. J.; Zheng, Q. D. Interfacial materials for organic solar cells: recent advances and perspectives. Adv. Sci. 2016, 3, 1500362. (2) Lin, X. F.; Yang, Y. Z.; Nian, L.; Su, H.; Ou, J. M.; Yuan, Z. K.; Xie, F. Y.; Hong, W.; Yu, D. S.; Zhang, M. Q.; et al. Interfacial modification layers based on carbon dots for efficient inverted polymer solar cells exceeding 10% power conversion efficiency. Nano Energy 2016, 26, 216-223. (3) Zou, J. Y.; Li, C. Z.; Chang, C. Y.; Yip, H. L.; Jen, A. K. Y. Interfacial Engineering of ultrathin metal film transparent electrode for flexible organic photovoltaic cells. Adv. Mater. 2014, 26, 3618-3623.

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(4) Yeo, J. S.; Kang, M.; Jung, Y. S.; Kang, R.; Lee, S. H.; Heo, Y. J.; Jin, S. H.; Kim, D. Y.; Na, S. I. In-depth considerations for better polyelectrolytes as interfacial materials in polymer solar cells. Nano Energy 2016, 21, 26-38. (5) He, Z. C.; Xiao, B.; Liu, F.; Wu, H. B.; Yang, Y. L.; Xiao, S.; Wang, C.; Russell, T. P.; Cao, Y. Single-junction polymer solar cells with high efficiency and photovoltage. Nat. Photon. 2015, 9, 174-179. (6) Ouyang, X. H.; Peng, R. X.; Ai, L.; Zhang, X. Y.; Ge, Z. Y. Efficient polymer solar cells employing a non-conjugated small-molecule electrolyte. Nat. Photon. 2015, 9, 520-524. (7) Jung, K.; Song, H. J.; Lee, G.; Ko, Y.; Ahn, K.; Choi, H.; Kim, J. Y.; Ha, K.; Song, J.; Lee, J. K.; et al. Plasmonic organic solar cells employing nanobump assembly via aerosol-derived nanoparticles. ACS Nano 2014, 8, 2590-2601. (8) Dai, A.; Zhou, Y. H.; Shu, A. L.; Mohapatra, S. K.; Wang, H.; Fuentes-Hernandez, C.; Zhang, Y. D.; Barlow, S.; Loo, Y. L.; Marder, S. R.; et al. Enhanced charge-carrier injection and collection via lamination of doped polymer layers p-doped with a dolution-processible molybdenum complex. Adv. Funct. Mater. 2014, 24, 2197-2204. (9) Feng, T.; Xiao, B.; Lv, Y.; Xie, Z. Q.; Wu, H. B.; Ma, Y. G. Domain-like ultra-thin layers deposited electrochemically from carbazole-functionalized perylene bisimides for electron collection in inverted photovoltaic cells. Chem. Commun. 2013, 49, 6283-6285 (10) Kim, J. S.; Park, J. H.; Lee, J. H.; Jo, J.; Kim, D. Y.; Cho, K. Control of the electrode work function and active layer morphology via surface modification of indium tin oxide for high efficiency organic photovoltaics. Appl. Phys. Lett. 2007, 91, 112111 (11) Chao, Y. H.; Wu, J. S.; Wu, C. E.; Jheng, J. F.; Wang, C. L.; Hsu, C. S. Solution-processed (Graphene oxide)-(d(0) transition metal oxide) composite anodic buffer layers toward high-performance and durable inverted polymer solar cells. Adv. Energy Mater. 2013, 3, 1279-1285

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(12) Yip, H. L.; Jen, A. K. Y. Recent advances in solution-processed interfacial materials for efficient and stable polymer solar cells. Energy Environ. Sci. 2012, 5, 5994-6011 (13) Chou, T. R.; Chen, S. H.; Chiang, Y. T.; Lin, Y. T.; Chao, C. Y. Highly conductive PEDOT:PSS films by post-treatment with dimethyl sulfoxide for ITO-free liquid crystal display. J. Mater. Chem. C 2015, 3, 3760-3766 (14) Oh, S. H.; Heo, S. J.; Yang, J. S.; Kim, H. J. Effects of ZnO nanoparticles on P3HT:PCBM organic solar cells with DMF-modulated PEDOT:PSS buffer layers. ACS Appl. Mater. Inter. 2013, 5, 11530-11534 (15) Lin, Y. J.; Ni, W. S.; Lee, J. Y. Effect of incorporation of ethylene glycol into PEDOT: PSS on electron phonon coupling and conductivity. J. Appl. Phys. 2015, 117, 215501 (16) Lin, Y. J.; Ni, W. S.; Lee, J. Y. Effect of incorporation of ethylene glycol into PEDOT: PSS on electron phonon coupling and conductivity. J. Appl. Phys. 2015, 118, 219901 (17) Yao, K.; Salvador, M.; Chueh, C.-C.; Xin, X.-K.; Xu, Y.-X.; de Quilettes, D. W.; Hu, T.; Chen, Y.; Ginger, D. S.; Jen, A. K. Y. A General route to enhance polymer solar cell performance using plasmonic nanoprisms. Adv. Energy Mater. 2014, 4, 1400206 (18) Hao, Y.; Song, J. C.; Yang, F.; Hao, Y. Y.; Sun, Q. J.; Guo, J. J.; Cui, Y. X.; Wang, H.; Zhu, F. R. Improved performance of organic solar cells by incorporating silica-coated silver nanoparticles in the buffer layer. J. Mater. Chem. C 2015, 3, 1082-1090 (19) Kitzke, T.; Nehrer, D.; Landfester, K.; Montenegro, R.; Guntner, R.; Scherf, U. Novel approaches to polymer blends based on polymer nanoparticles. Nat. Mater. 2003, 2, 408 (20) Preinfalk, J. B.; Schackmar, F. R.; Lampe, T.; Egel, A.; Schmidt, T. D.; Brutting, W.; Gomard, G.; Lemmer, U. Tuning the microcavity of organic light emitting diodes by solution processable polymer-nanoparticle composite layers. ACS Appl. Mater. Inter. 2016, 8, 2666-2672 13



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(21) Zhang, S.; Shao, Y. Y.; Liu, J.; Aksay, I. A.; Lin, Y. H. Graphene-polypyrrole nanocomposite as a highly efficient and low cost electrically switched ion exchanger for removing ClO4- from Wastewater. ACS Appl. Mater. Inter. 2011, 3, 633-3637 (22) Guo, F. M.; Xu, R. Q.; Cui, X.; Zhang, L.; Wang, K. L.; Yao, Y. W.; Wei, J. Q. High performance

of

stretchable

carbon nanotube-polypyrrole

fiber

supercapacitors under dynamic deformation and temperature variation. J. Mater. Chem. A 2016, 4, 9311-9318 (23) Garcia-Cordova, F.; Valero, L.; Ismail, Y. A.; Otero, T. F. On the ozone degradation of polypyrrole. Polym. Degrad. Stab. 2003, 82, 487 (24) Wang, Q.; Chueh, C. C.; Eslamina, M.; Jen, A. K. Y. Modulation of PEDOT:PSS pH for efficient inverted perovskite solar cells with reduced potential loss and enhanced stability. ACS Appl. Mater. Inter. 2016, 8, 32068-32076 (25) Noh, Y. J.; Park, S. M.; Yeo, J. S.; Kim, D. Y.; Kim, S. S.; Na, S. I. Efficient PEDOT:PSS-free polymer solar cells with an easily accessible polyacrylonitrile polymer material as a novel solution-processable anode interfacial layer. ACS Appl. Mater. Inter. 2015, 7, 25032

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Scheme 1 a) Device structures of PSCs and the molecular structures of polypyrrole (PPy) and PEDOT:PSS; b) Energy level diagram of the state-of-the-art photovoltaic materials; c) The chemical structures of P3HT, PTB7, and PC71BM. Figure 1 a) Solubility and mechanism of water soluble PPy NPs; b) FTIR spectra of these soluble PPy and insoluble PPy; c) SEM images of PPy NPs with the polymerized time of 1 h; d) SEM images of PPy NPs with the polymerized time of 10 h. Figure 2 a) Transmittance spectra of the different doped concentrations of PPy NPs (0, 5%, 15%, 20%, 25%) on the quartz glass; b) The conductivities of the different doped concentrations of PPy NPs (0, 5%, 15%, 20%, 25%) on bare glass and pH changes versus the doping ratio. Figure 3. a) tapping-mode atomic force microscopy (AFM) topographic images of pristine PEDOT:PSS; b) AFM three-dimensional (3D) surface plot of pristine PEDOT:PSS; c) AFM phase images of pristine PEDOT:PSS; d) AFM topographic images of 20% PPy NPs doped PEDOT:PSS; e) 3D surface plot of 20% PPy NPs doped PEDOT:PSS; f) AFM phase images of 20% PPy NPs doped PEDOT:PSS; g) UPS spectra of PEDOT:PSS and 20% PPy NPs doped PEDOT:PSS films. Figure 4. a) Current density versus voltage (J-V) characteristics with the active-layer of PTB7:PC71BM; b) J-V characteristics with the active-layer of P3HT:PC61BM; c) The external quantum curves of devices based on PTB7:PC71BM; d) The external quantum curves of devices based on P3HT:PC61BM. Figure 5. Lifetime measurement of devices based on PTB7:PC71BM.

Table 1. Some important parameters for PSCs with or without various interfacial materials (device area: 9.0 mm2)

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Scheme 1

Figure 1

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Figure 2

Figure 3

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Figure 4

Figure 5

10 9 8 7

PCE (%)

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6

PPy-PEDOT:PSS PEDOT:PSS none

5 4

3 0

10

20

30

Times (day) 18


40

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Table 1

a

the average PCE was derived from 50 parallel devices.

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TOC Graphic

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