A single polymeric template-based full color organic electrochromic

Subscriber access provided by SWINBURNE UNIV OF TECHNOLOGY

Applications of Polymer, Composite, and Coating Materials

A single polymeric template-based full color organic electrochromic device Hui Zhang, Shouli Ming, Yuzhang Liang, Lei Feng, Alec Talin, and Ting Xu ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.8b21215 • Publication Date (Web): 01 Feb 2019 Downloaded from http://pubs.acs.org on February 3, 2019

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Materials & Interfaces

A Single Polymeric Template-based Full Color Organic Electrochromic Device Hui Zhang†,1, Shouli Ming§,1, Yuzhang Liang†, Lei Feng†, Alec Talin‡,*, Ting Xu†,* †

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and

Collaborative Innovation Centre of Advanced Microstructures, Nanjing University, Nanjing 210093, China ‡

Sandia National Laboratories, Livermore, CA 94551, USA

§

Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing

Normal University, Beijing 100875, China.

ABSTRACT: With low-cost and simple processing, organic electrochromic polymers have attracted considerable attention as a promising material platform for flexible and low-energyconsuming optoelectronic devices. However, typical electrochromic polymers can only be switched from natural-colored to oxidized-transparent states. As a result, the complexity of combining several distinct polymers to achieve a full-color gamut has significantly limited the niche applications of electrochromic polymers. Here we report an electrochromic polymer based

on

4,7-di((3,3-dimethyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine-3-yl)-3,4-

ethylenedioxythiophene) (PEP), which exhibits fast full-color reversible tuning capability and good stability. Furthermore, a red-green-blue flexible electrochromic device just based on poly(PEP) was fabricated, which offers an effective approach to dynamically manipulate color and enables a variety of optoelectronic applications. KEYWORDS: full-color tuning, single molecular template, conjugated polymer, electrochromic material, electrochromic device.

1

ACS Paragon Plus Environment

ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1. INTRODUCTION Electrochromic materials, which show a reversible color change when reduced or oxidized electrochemically by application of a small voltage, have generated much interest in academia and industry for their fascinating spectroelectrochemical properties and practical applications [1-4]. In contrast to the complexity and high-cost of thin film vacuum deposition typically required in fabrication of inorganic electrochromic devices, such as tungsten trioxide, the solution-process technology endows conjugated polymers for the mass production of flexible and cost-effective electrochromic materials [5-10]. Therefore, polymer electrochromic devices are particularly attractive for retrofitting onto existing windows for energy savings, as well as for a variety of wearable medical and fashion related applications [11-13]. But unfortunately, most of the typical conjugated polymers, such as poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3,4-propyylenedioxythiophene) (PProDOT), can only be switched from naturalcolored to oxidized-transparent states [7,14,15]. The monotony of generated colors significantly limits their extended colorful electrochromic applications in the visible spectrum [16,17]. As an important factor to evaluate the performance of electrochromic materials, color gamut directly links to the human visual perception and determines electrochromic materials’ application scenarios [18,19]. To achieve the electrochromic devices displaying several different colors, most researchers assemble two (or more) kinds of electrochromic materials together to increase the color gamut according to color-mixing theory principles [20-28]. However, the complicated process and the chemical compatibility between different electrochromic materials restrict their practical applications. Compared to processing techniques based on color-mixing theory, different colors of designed polymers have been achieved through incorporation of donor-acceptor system, modification of steric effects, introduction of heteroatom, etc. [18, 29-30]. As an alternative method, recently, single

2


Page 2 of 24

Page 3 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


polymer-based full-color electrochromics have been achieved by employing plasmonic nanostructured electrodes [31]. The working principle of this approach is to use surface plasmon polaritons of nanostructured electrode to filter the spectrum of white light and generate individual colors. Nevertheless, the high-cost associated with fabrication of largescale nanostructured electrodes represents a significant challenge for mass production. Our previous work demonstrated that conjugated polymers with planar skeleton exhibit excellent electrochromic performance [30]. It was noteworthy that planar conjugated system can be maintained through intramolecular noncovalent interactions, such as O···S. Considering the O···S interaction between the adjacent EDOT and ProDOT, we designed and synthesized the

conjugated

polymer

poly(4,7-di((3,3-dimethyl-3,4-dihydro-2H-thieno[3,4-

b][1,4]dioxepine-3-yl)-3,4-ethylenedioxythiophene)) (poly(PEP)) with full-color tenability where colors form a closed loop in the CIE chromaticity diagram. Then, red-green-blue (RGB) solid-state electrochromic device was fabricated only based on poly(PEP). To our knowledge, this is the first report on the single polymeric template-based RGB organic electrochromic device. In addition, poly(PEP) exhibits excellent electrochemical and optical stability. Therefore, this single polymeric template-based electrochromic device offers an effective way to dynamically manipulate the color spectrum in the visible range and potentially enabling a myriad of optoelectronic applications. 2. RESULTS AND DISCUSSION Synthesis of poly(PEP). Scheme 1 shows the synthetic route and electropolymerization of 4,7-di((3,3-dimethyl-3,4-dihydro-2H-thieno[3,4-b][1,4]

dioxepine-3-yl)-3,4-

ethylenedioxythiophene) (PEP). Compounds 3 and 6 were prepared by previous literature procedure [30, 32]. The removal of one α-proton at Compound 3 with n-BuLi afforded the anion intermediate, which was quenched by Bu3SnCl to obtain the Compound 4, which was used for the next step without further purification. Followed by one-step Stille coupling of 3



Compounds 4 and 6, the desired monomer PEP was obtained with a yield of 20%. PEP exhibits high solubility in common organic solvents, such as dichloromethane (DCM) and acetonitrile (ACN). Finally, the poly(PEP) was electrochemical polymerized in 0.1 M ACN-Bu4NPF6 at room temperature. The details and characterizations are provided in the supporting information (SI). Electrochemical properties of poly(PEP). Figure 1a displays the recorded cyclic voltammograms (CVs) during the potentiodynamic electrochemical polymerization of PEP. The onset oxidation potential of PEP was 0.56 V according to the first cycle of CVs in Figure 1a, which was greatly lowered compared with typical thiophene derivatives, implying that electropolymerization of PEP was feasible in acetonitrile. The represent growth of anodic and cathodic peak current densities demonstrated that the amount of the polymer depositing on the electrode surface increased. Also, the broad redox peaks of the polymer were observed during polymerization process, which could be ascribed to the wide distribution of polymer chain length and the mutual transition of conductive species in different states (including neutral state, polaron, bipolaron and metallic state) [30, 33-35]. And, the potential shift of current density peaks was also shown during polymer deposition, which provided the information: 1) the increase in the electrical resistance of the polymer; 2) the extra potential was needed to overcome this resistance. For further investigate the electrochemical behaviors of poly(PEP), a polymer-coated ITO electrode was studied by cyclic voltammetry in monomer-free ACN-Bu4NPF6 (0.1 mol L-1). The CVs of poly(PEP) exhibited broad anodic and cathodic peaks, as shown in Figure 1b. Since the current densities of anodic peaks (jp,a) and cathodic peaks (jp,c) were linearly proportional to the scan rate (Figure 1c), it could be concluded that the polymer was adhered to the working electrode surface and the redox process of poly(PEP) was non-diffusion controlled [36-38]. It is noteworthy that the electrochemical stability of polymer is an essential

4


Page 4 of 24

Page 5 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


requirement for practical applications. For that reason, the cycling stability of poly(PEP) was investigated in monomer-free ACN-Bu4NPF6 (0.1 mol L-1) solution, as shown in Figure S1. The electrochemical activity of poly(PEP) retained up to 86% after 5000 cycles (Table S1), which implied the excellent cycling stability of poly(PEP). Electrochromic properties of poly(PEP). As the applied voltages vary, the doping degree of electrochromic polymer is different, which results in the energy band and optical absorption varying. Meanwhile, the electrochromic material shows color change from the appearance. Therefore, the absorption spectra of poly(PEP) were measured under different applied potentials ranging from -0.7 V to 0.6 V as shown in Figure 2a. Similar to PEDOT derivatives, poly(PEP) in the neutral state exhibits a dominant absorption band centered around 550 nm, which could be attributed to π-π* transitions of thiophene rings [14, 25, 38]. When the applied potential gradually increases from -0.7 V to 0.6 V, the absorption band shifts to nearinfrared region, which results from the decreased valence intensity of π-π* transition and the formation of polaronic and biopolaronic carriers on the polymer backbone [18, 30]. In contrast to the conventional electrochromic materials switching from natural-colored to oxidizedtransparent states, the poly(PEP) has several stable intermediate states as the applied potential increasing from -0.7 V to 0.6 V, exhibiting different colors including purple, red, orange, yellow, yellowish green, green, cyan and blue (Figure 2b). For better quantifying the colors of poly(PEP) films, all the measured colors were mapped into a CIE 1976 chromaticity diagram, as show in Figure 2c. It can be clearly seen that all the color coordinates form a closed loop in the chromaticity diagram, further proving that poly(PEP) film could be regard as a real single polymeric template based full-color tunable electrochromic material. According to Figure S6, the electrochromic parameters of poly(PEP) including optical contrast ratio (T) and response time were summarized in Table S2. Poly(PEP) showed 41%

5



optical contrast in the visible region (550 nm). The transmittance of poly(PEP) were 27% at reduction state and 68% at oxidation state, respectively. It was noteworthy that poly(PEP) exhibited fast switching speed in reduction and oxidation processes (reduction: 0.2 s; oxidation: 0.4 s). The optical stability is an important parameter for the application of electrochromic materials. Here, the optical stability of poly(PEP) was measured in monomer-free ACNBu4NPF6 (without any seal). Figure S7 shows the measured transmittance of the poly(PEP) film at 550 nm between -0.7 V ~ 0.6 V. After sweeping 6100 cycles over a period of 17 hours, the value of T held at 39.75%, without any significant decline compared with its initial state (T=40.88%). The result indicated that poly(PEP) has promising long-term optical stability, which was in good agreement with the electrochemical result (Table S1). Meanwhile, the switching speed of poly(PEP) film kept 0.8 s in oxidation process. These results indicate that poly(PEP) film has promising long-term optical stability and fast switching speed. Poly(PEP)-based flexible RGB electrochemical device. In order to validate the feasibility of the single polymeric template for practical applications, a typical flexible electrochromic device was assembled based on poly(PEP), as shown in Figure 3a. Figure 3b-d are the actual color images of the flexible device under three different potentials, exhibiting three complementary colors red (R, -1.5 V), green (G, 0.7 V), and blue (B, 2.0 V). This applied voltage range was a little higher than that in ACN-Bu4NPF6 electrolyte. The phenomenon could be attributed to many factors such as low ionic conductivity of gel electrolyte and effective area of device. For better evaluating the performance of the fabricated device, switching time and coloration efficiency ( CE) of the RGB devices were measured at the wavelength of 550 nm with a time step of 5 s. Figure 4 shows the current-time response (Figure 4a) and transmittance-time profile (Figure 4b) of the “DISPLAY” device.

6


Page 6 of 24

Page 7 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Compare to poly(PEP) film in the liquid electrolyte, the DISPLAY device exhibited longer switching times. The switching time of the DISPLAY device were determined to be 3.8 s and 2.6 s (R↔G), 3.4 s and 2.3 s (R↔B), 4.5 s and 4.1s (G↔B), respectively. Also, the coloration efficiency ( CE) of DISPLAY device was calculated by the following equation [39, 40]:

𝐶𝐸 =

∆OD 𝑄

∆OD = log

(1)

[ ] (2) 𝑇𝑏 𝑇𝑐

Where Q is the injected/ejected charge per unit of the electrochromic material area, Tb and Tc indicate the transmittance in bleached and colored state, respectively. The optical density (OD) is determined using T% values of the corresponding potentials. According to the above equation, the CE values between red and green (R↔G), red and blue (R↔B), green and blue (G↔B) were 452 cm2 C-1, 385 cm2 C-1, 587 cm2 C-1, respectively. This result demonstrated that the device could realize a wide range of optical modulation in the visible spectral regime with less energy. 3. CONCLUSION In summary, a single polymeric template-based organic electrochromic material poly(PEP) was synthesized, which shows “full-color” (purple, red, orange, yellow, yellowish green, green, cyan and blue) reversible tuning capability, good electrochemical activity and long-term stability. Also, we fabricated a flexible, solid-state RGB electrochromic device based on the synthesized polymer. As an effective approach to dynamically manipulate colors, the single polymeric template-based electrochromic material is promising for a variety of low-cost optoelectronic and environment-friendly applications.

7



ASSOCIATED CONTENT Supporting Information Detailed experiment results of quantum chemical calculations, monomer synthesis, electrochromic experiment, SEM, FTIR, 1H NMR, 13C NMR, HRMS, etc. AUTHOR INFORMATION Corresponding Authors *Email: [email protected] *Email: [email protected] ORCID Ting Xu: 0000-0002-0704-1089 Author Contributions 1

These authors contributed equally to this work.

Notes The authors declare no competing financial interest. ACKNOWLEDGEMENTS The work is supported in part by the National Key R&D Program of China under Grant No. 2017YFA0303700 and 2016YFA0202100, National Natural Science Foundation of China (61575092 and 11774163), Fundamental Research Funds for Central Universities under Grant No. 14380078. REFERENCCES 1. Deb, S.; Chopoorian, J. Optical Properties and Color-Center Formation in Thin Films of Molybdenum Trioxide. J. Appl. Phys. 1966, 37, 4818-4825. 2. Deb, S. A Novel Electrophotographic System. Appl. Opt. 1969, 8, 192-195. 3. Argun, A.; Aubert, P.; Thompson, B.; Schwendeman, I.; Gaupp, C.; Hwang, J.; Pinto, N.;

8


Page 8 of 24

Page 9 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Tanner, D.; Macdiarmid, A.; Reynolds, J. Multicolored Electrochromism in Polymers: Structures and Devices. Chem. Mater. 2004, 16, 4401-4412. 4. Otley, M.; Alamer, F.; Zhu, Y.; Singhaviranon, A.; Zhang, X.; Li, M.; Kumar, A.; Sotzing, G. Acrylated Poly (3,4-Propylenedioxythiophene) for Enhancement of Lifetime and Optical Properties for Single-Layer Electrochromic Devices. ACS Appl. Mater. Interfaces 2014, 6, 1734-1739. 5. Kumar, A.; Welsh, D.; Morvant, M.; Piroux, F.; Abboud, K.; Reynolds, J. Conducting Poly(3,4-Alkylenedioxythiophene) Derivatives as Fast Electrochromics with HighContrast Ratios. Chem. Mater. 1998, 10, 896-902. 6. GÉLinas, B.; Das, D.; Rochefort, D. Air-Stable, Self-Bleaching Electrochromic Device based on Viologen-and Ferrocene-Containing Triflimide Redox Ionic Liquids. ACS Appl. Mater. Interfaces 2017, 9, 28726-28736. 7. Mortimer, R.; Dyer, A.; Reynolds, J. Electrochromic Organic and Polymeric Materials for Display Applications. Displays 2006, 27, 2-18. 8. Groenendaal,

L.;

Jonas,

F.;

Freitag,

D.;

Pielartzik,

H.;

Reynolds,

J.

Poly(3,4‐Ethylenedioxythiophene) and its Derivatives: Past, Present, and Future. Adv. Mater. 2000, 12, 481-494. 9. Sonmez, G.; Meng, H.; Wudl, F. Organic Polymeric Electrochromic Devices: Polychromism with Very High Coloration Efficiency. Chem. Mater. 2004, 16, 574-580. 10. Groenendaal, L.; Zotti, G.; Aubert, P.; Waybright, S.; Reynolds, J. Electrochemistry of Poly(3,4‐Alkylenedioxythiophene) Derivatives. Adv. Mater. 2003, 15, 855-879. 11. Davy, N.; Sezen-Edmonds, M.; Gao, J.; Lin, X.; Liu, A.; Yao, N.; Kahn, A.; Loo, Y. Pairing Of Near-Ultraviolet Solar Cells with Electrochromic Windows for Smart Management of the Solar Spectrum. Nat. Energy 2017, 2, 17104. 12. Eh, A.; Tan, A.; Cheng, X.; Magdassi, S.; Lee, P. Recent Advances in Flexible

9



Electrochromic Devices: Prerequisites, Challenges, and Prospects. Energy Technology 2018, 6, 33-45. 13. He, J.; Mukherjee, S.; Zhu, X.; You, L.; Boudouris, B.; Mei, J. A Highly Transparent Crosslinkable Radical Copolymer Thin Film as the Ion Storage Layer in Organic Electrochromic Devices. ACS Appl. Mater. Interfaces 2018, 10, 18956-18963. 14. Dey, T.; Invernale, M.; Ding, Y.; Buyukmumcu, Z.; Sotzing, G. Poly(3,4Propylenedioxythiophene)s as a Single Platform for Full Color Realization. Macromolecules 2011, 44, 2415-2417. 15. Pei, Q.; Zuccarello, G.; Ahlskog, M.; Inganäs, O. Electrochromic and Highly Stable Poly(3,4-Ethylenedioxythiophene) Switches between Opaque Blue-Black and Transparent Sky Blue. Polymer 1994, 35, 1347-1351. 16. Sonmez, G.; Wudl, F. Completion of the Three Primary Colours: The Final Step Toward Plastic Displays. J. Mater. Chem. 2005, 15, 20-22. 17. Tehrani, P.; Hennerdal, L.; Dyer, A.; Reynolds, J.; Berggren, M. Improving the Contrast of All-Printed Electrochromic Polymer on Paper Displays. J. Mater. Chem. 2009, 19, 17991802. 18. Beaujuge, P.; Reynolds, J. Color Control in Π-Conjugated Organic Polymers for use in Electrochromic Devices. Chem. Rev. 2010, 110, 268-320. 19. Beverina, L.; Pagani, G.; Sassi, M. Multichromophoric Electrochromic Polymers: Colour Tuning of Conjugated Polymers Through the Side Chain Functionalization Approach. Chem. Commun. 2014, 50, 5413-5430. 20. Scrosati, B. Applications of Electroactive Polymers. London: Chapman & Hall, 1993. 21. Somani, P.; Radhakrishnan, S. Electrochromic Materials and Devices: Present and Future. Mater. Chem. Phys. 2003, 77, 117-133.

10


Page 10 of 24

Page 11 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


22. Kim, J.; You, J.; Kim, B.; Park, T.; Kim, E. Solution Processable and Patternable Poly(3,4Alkylenedioxythiophene)s for Large‐Area Electrochromic Films. Adv. Mater. 2011, 23, 4168-4173. 23. Baeriswyl, D.; Campbell, D.; Clark, G.; Harbeke, G.; Kahol, P.; Kiess, H.; Mazumdar, S.; Mechring, M.; Rehwald, W. Conjugated Conducting Polymers. Springer Science & Business Media, 2012. 24. Alamer, F.; Otley, M.; Ding, Y.; Sotzing, G. Solid‐State High‐Throughput Screening for Color Tuning of Electrochromic Polymers. Adv. Mater. 2013, 25, 6256-6260. 25. Karabiyik, E.; Sefer, E.; Baycan Koyuncu, F.; Tonga, M.; ÖZdemir, E.; Koyuncu, S. Toward Purple-to-Green-to-Transmissive-to-Black Color Switching in Polymeric Electrochrome. Macromolecules 2014, 47, 8578-8584. 26. Oh, H.; Seo, D.; Yun, T.; Kim, C.; Moon, H. Voltage-Tunable Multicolor, Sub-1.5 V, Flexible Electrochromic Devices based on Ion Gels. ACS Appl. Mater. Interface 2017, 9, 7658-7665 27. Wan, Z.; Zeng, J.; Li, H.; Liu, P.; Deng, W. Multicolored, Low‐Voltage‐Driven, Flexible Organic Electrochromic Devices based on Oligomers. Macromol. Rapid Commun. 2018, 39, 1700886. 28. Lahav, M.; Van Der Boom, M. Polypyridyl Metallo‐Organic Assemblies for Electrochromic Applications. Adv. Mater. 2018, 30, 1706641. 29. Kerszulis, J.; Johnson, K.; Kuepfert, M.; Khoshabo, D.; Dyer, A.; Reynolds, J. Tuning The Painter's Palette: Subtle Steric Effects on Spectra and Colour in Conjugated Electrochromic Polymers. J. Mater. Chem. C 2015, 3, 3211-3218. 30. Lu, B.; Zhen, S.; Zhang, S.; Xu, J.; Zhao, G. Highly Stable Hybrid Selenophene-3,4Ethylenedioxythiophene as Electrically Conducting and Electrochromic Polymers. Polym. Chem. 2014, 5, 4896-4908.

11



31. Xu, T.; Walter, E.; Agrawal, A.; Bohn, C.; Velmurugan, J.; Zhu, W.; Lezec, H.; Talin, A. High-Contrast and Fast Electrochromic Switching Enabled by Plasmonics. Nat. Commun. 2016, 7, 10479. 32. Welsh, D.; Kumar, A.; Meijer, E.; Reynolds, J. Enhanced Contrast Ratios and Rapid Switching in Electrochromics based on Poly (3, 4‐Propylenedioxythiophene) Derivatives. Adv. Mater. 1999, 11, 1379-1382. 33. Ming, S.; Zhen, S.; Lin, K.; Zhao, L.; Xu, J.; Lu, B. Thiadiazolo[3,4-c]pyridine as an Acceptor Toward Fast-Switching Green Donor-Acceptor-Type Electrochromic Polymer with Low Bandgap. ACS Appl. Mater. Interfaces 2015, 7, 11089-11098. 34. Ming, S.; Zhen, S.; Liu, X.; Lin, K.; Liu, H.; Zhao, Y.; Lu, B.; Xu, J. Chalcogenodiazolo[3,4-c]pyridine based Donor-Acceptor-Donor Polymers for Green and Near-Infrared Electrochromics. Polym. Chem. 2015, 6, 8248-8258. 35. Elschner, A.; Kirchmeyer, S.; Lovenich, W.; Merker, U.; Reuter, K. PEDOT: Principles and Applications of an Intrinsically Conductive Polymer. CRC Press, 2010. 36. Sönmez, G.; Schwendeman, I.; Schottland, P.; Zong, K.; Reynolds, J. N-Substituted Poly(3,4-Propylenedioxypyrrole)s: High Gap and Low Redox Potential Switching Electroactive and Electrochromic Polymers. Macromolecules 2003, 36, 639-647. 37. Toksabay, S.; Hacioglu, S.; Unlu, N.; Cirpan, A.; Toppare, L. Thieno[3,2-b]thiophene as Π-Bridge at Different Acceptor Systems for Electrochromic Applications. Polymer 2014, 55, 3093-3099. 38. Nie, G.; Wang, L.; Liu, C. High Performance Electrochromic Devices based on a Polyindole Derivative, Poly (1H-benzo[g]indole). J. Mater. Chem. C 2015, 3, 11318-11325. 39. Thakur, V.; Ding, G.; Ma, J.; Lee, P.; Lu, X. Hybrid Materials and Polymer Electrolytes for Electrochromic Device Applications. Adv. Mater. 2012, 24, 4071-4096. 40. Lin, S.; Bai, X.; Wang, H.; Wang, H.; Song, J.; Huang, K.; Wang, C.; Wang, N.; Li, B.;

12


Page 12 of 24

Page 13 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Lei, M.; Wu, H. Roll-to-Roll Production of Transparent Silver-Nanofiber-Network Electrodes for Flexible Electrochromic Smart Windows. Adv. Mater. 2017, 29, 1703238.

13



Page 14 of 24

Figure

OH

O

Br

O S

O

ii O

S

O S

v

Br

S Sn

iv

O

O

O S

S

n

O

O

poly(PEP)

O 4

O

6

O

3

S

O

iii

5

S

O

2

S

O

O

i

S

1

O

O

O

OH

O S

O

PEP

Scheme 1 Synthetic route of poly(PEP); (i) p-TSA, toluene, 80oC, 56%; (ii) n-BuLi, THF, -78oC; Bu3SnCl, -40oC; (iii) NBS, CH3COOH/CHCl3, 85%; (iv) Pd(PPh3)4, THF, refluxing, 20%; (v) ACN-Bu4NPF6, electrochemical polymerization.

14


Page 15 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 1 (a) CVs of PEP (0.05 mol L-1) in ACN-Bu4NPF6 (0.1 mol L-1) solution at the potential scan rate of 100 mV s-1; (b) CVs of poly(PEP) in monomer-free ACN-Bu4NPF6 (0.1 mol L-1) solution, potential scan rates: 15 ~ 300 mV s-1; (c) plots of redox peak current densities as a function of potential scan rates.

15



Figure 2 (a) Absorption spectra of poly(PEP) in the potential range from -0.7 V to 0.6 V with a step of 0.05 V; (b) color changes and (c) corresponding color coordinates of poly(PEP) at different potentials: (1) -0.50 V, (2) -0.41 V, (3) -0.25 V, (4) -0.20 V, (5) 0.10 V, (6) 0.18 V, (7) 0.35 V, (8) 0.45 V.

16


Page 16 of 24

Page 17 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 3 (a) Schematic diagram of the flexible poly(PEP)-based electrochromic device; (b)-(d) Color changes of the electrochromic device under different applied potentials.

17



Figure 4 (a) Current-time response and (b) transmittance-time profile of the device between R↔B (the black dotted line), R↔G (the purple dashed line), G↔B (the blue dashed line) at 550 nm.

18


Page 18 of 24

Page 19 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Scheme 1 170x178mm (300 x 300 DPI)



Fig.1 391x113mm (300 x 300 DPI)


Page 20 of 24

Page 21 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Fig. 2 238x240mm (300 x 300 DPI)



Fig.3


Page 22 of 24

Page 23 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Fig. 4 315x131mm (300 x 300 DPI)


ACS Applied Materials & Interfaces 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52


Page 24 of 24

A single polymeric template-based full color organic electrochromic

Recommend Documents