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Ji J, Wu Z, Xie J, Wang W, Qian H, Liang Z. Dual Polymerized Y-Acceptors of Distinct-Dimensionality Create Neuron-Like Interpenetrating Hierarchical Network towards Efficient and Stable All-Polymer Solar Cells. Adv Mater 2024; 36:e2313237. [PMID: 38214364 DOI: 10.1002/adma.202313237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Indexed: 01/13/2024]
Abstract
All-polymer solar cells have garnered particular attention thanks to their superior thermal, photo, and mechanical stabilities for large-scale manufacturing, yet the performance enhancement remains largely restrained by inherent morphological challenges of the bulk-heterojunction active layer. Herein, a 3D Y-branched polymerized small-molecule acceptor named PYBF, characteristic of high molecular weight and glass transition temperature, is designed and synthesized by precisely linking C3h-symmetric benzotrifuran with Y6 acceptors. In comparison to the benchmark thiophene-bridged linear PYIT acceptor, an optical blue-shift absorption is observed for PYBF yet a slightly higher power conversion efficiency (PCE) of 15.7% (vs 15.14%) is obtained when paired with polymer donor PM6, which benefit from the more crystalline and face-on-oriented PYBF domains. However, the star-like bulky structure of PYBF results in the nucleation-growth dominant phase-separation in polymeric blends, which generates stumpy droplet-like acceptor fibrils and impairs the continuity of acceptor phases. This issue is however surprisingly resolved by incorporating a small amount of PYIT, which leads to the formation of the more interconnective neuron-like dual-acceptor domains by long-chain entanglements of linear acceptors and alleviates bimolecular recombination. Thus, the champion device realizes a respectable PCE of up to ≈17% and importantly exhibits thermal and storage stabilities superior to the linear counterpart.
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Affiliation(s)
- Jingjing Ji
- Department of Materials Science, Fudan University, Shanghai, 200433, China
| | - Zhiyuan Wu
- Department of Materials Science, Fudan University, Shanghai, 200433, China
| | - Jiaqi Xie
- Department of Materials Science, Fudan University, Shanghai, 200433, China
| | - Weiyi Wang
- Research Center for Molecular Recognition and Synthesis, Department of Chemistry, Fudan University, Shanghai, 200433, China
| | - Hui Qian
- Research Center for Molecular Recognition and Synthesis, Department of Chemistry, Fudan University, Shanghai, 200433, China
| | - Ziqi Liang
- Department of Materials Science, Fudan University, Shanghai, 200433, China
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Ji J, Zhu L, Xiong X, Liu F, Liang Z. Developing Y-Branched Polymer Acceptor with 3D Architecture to Reconcile Between Crystallinity and Miscibility Yielding >15% Efficient All-Polymer Solar Cells. Adv Sci (Weinh) 2022; 9:e2200864. [PMID: 35595683 PMCID: PMC9313542 DOI: 10.1002/advs.202200864] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 04/13/2022] [Indexed: 06/15/2023]
Abstract
In all-polymer solar cells (all-PSCs), there remains such a dilemma that obtains good miscibility and crystallinity simultaneously. Herein a new family of Y-shape polymer acceptor, namely PYTT is developed, which is copolymerized from Y6 and benzotrithiophene units in three-way directions. Benefiting from its high-density end-chains and extended π-conjugation thanks to highly-branched 3D architecture, PYTT displays better organic solubility despite much higher molecular weights, larger crystallinity, and tighter π-stacking than the linear counterpart-PYT comprising Y6 and thiophene moieties, while showing identical optical absorption yet threefold higher photoluminescence intensity. In PYTT blend film with PM6 polymer donor, the interpenetrating nano-fibrillar structures are formed with well-intermixed polymeric domain sizes close to the exciton diffusion length, which is greatly conducive to exciton dissociation and charge transport in device. Consequently, PYTT-based all-PSCs exhibit all increased photovoltaic parameters, yielding a decent power conversion efficiency of 15.60%, which is ≈20% enhancement over PYT-based device, along with low nonradiative loss of 0.221 meV.
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Affiliation(s)
- Jingjing Ji
- Department of Materials ScienceFudan UniversityShanghai200433China
| | - Lei Zhu
- School of Chemistry and Chemical EngineeringFrontiers Science Center for Transformative MoleculesIn Situ Center for Physical Science and Center of Hydrogen ScienceShanghai Jiao Tong UniversityShanghai200240China
| | - Xia Xiong
- School of Chemical and Environmental EngineeringShanghai Institute of TechnologyShanghai201418China
| | - Feng Liu
- School of Chemistry and Chemical EngineeringFrontiers Science Center for Transformative MoleculesIn Situ Center for Physical Science and Center of Hydrogen ScienceShanghai Jiao Tong UniversityShanghai200240China
| | - Ziqi Liang
- Department of Materials ScienceFudan UniversityShanghai200433China
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You H, Lee S, Kim D, Kang H, Lim C, Kim FS, Kim BJ. Effects of the Selective Alkoxy Side Chain Position in Quinoxaline-Based Polymer Acceptors on the Performance of All-Polymer Solar Cells. ACS Appl Mater Interfaces 2021; 13:47817-47825. [PMID: 34590813 DOI: 10.1021/acsami.1c12288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The effects of the position of alkoxy side chains in quinoxaline (Qx)-based polymer acceptors (PAs) on the characteristics of materials and the device parameters of all-polymer solar cells (all-PSCs) are investigated. The alkoxy side chains are selectively located at the meta, para, and both positions in pendant benzenes of Qx units, constructing PAs denoted as P(QxCN-T2)-m, P(QxCN-T2)-p, and P(QxCN-T2), respectively. Among them, P(QxCN-T2)-m exhibits the deepest energy levels owing to the enhanced electron-withdrawing effect of meta-positioned alkoxy chains, which is in contrast to P(QxCN-T2)-p where para-positioned alkoxy chains have an electron-donating property. In addition, the meta-positioned alkoxy chains induce good electron-conducting pathways, while the para-positioned ones significantly interrupt crystallization and intermolecular interactions between the conjugated backbones. Thus, when the PAs are applied to all-PSCs, a power conversion efficiency (PCE) of 5.07% is attained in the device using P(QxCN-T2)-m with efficient exciton dissociation and good electron-transporting ability. On the contrary, the P(QxCN-T2)-p-based counterpart has a PCE of only 1.62%. These results demonstrate that introducing alkoxy side chains at a proper location in the Qx-based PAs is crucial for their application to all-PSCs.
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Affiliation(s)
- Hoseon You
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Seungjin Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Donguk Kim
- School of Chemical Engineering and Materials Science, Chung-Ang University (CAU), Seoul 06974, Republic of Korea
| | - Hyunbum Kang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Chulhee Lim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Felix Sunjoo Kim
- School of Chemical Engineering and Materials Science, Chung-Ang University (CAU), Seoul 06974, Republic of Korea
| | - Bumjoon J Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
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You H, Kang H, Kim D, Park JS, Lee JW, Lee S, Kim FS, Kim BJ. Cyano-Functionalized Quinoxaline-Based Polymer Acceptors for All-Polymer Solar Cells and Organic Transistors. ChemSusChem 2021; 14:3520-3527. [PMID: 33655716 DOI: 10.1002/cssc.202100080] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/05/2021] [Indexed: 06/12/2023]
Abstract
Quinoxaline (Qx) derivatives are promising building units for efficient photovoltaic polymers owing to their strong light absorption and high charge-transport abilities, but they have been used exclusively in the construction of polymer donors. Herein, for the first time, Qx-based polymer acceptors (PA s) were developed by introducing electron-withdrawing cyano (CN) groups into the Qx moiety (QxCN). A series of QxCN-based PA s, P(QxCN-T2), P(QxCN-TVT), and P(QxCN-T3), were synthesized by copolymerizing the QxCN unit with bithiophene, (E)-1,2-di(thiophene-2-yl)ethene, and terthiophene, respectively. All of the PA s exhibited unipolar n-type characteristics with organic field-effect transistor (OFET) mobilities of around 10-2 cm2 V-1 s-1 . In space-charge-limited current devices, P(QxCN-T2) and P(QxCN-TVT) exhibited electron mobilities greater than 1.0×10-4 cm2 V-1 s-1 , due to the well-ordered structure with tight π-π stacking. When the PA s were applied in all-polymer solar cells (all-PSCs), the highest performance of 5.32 % was achieved in the P(QxCN-T2)-based device. These results demonstrate the significant potential of Qx-based PA s for high-performance all-PSCs and OFETs.
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Affiliation(s)
- Hoseon You
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Hyunbum Kang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Donguk Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Jin Su Park
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Jin-Woo Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Seungjin Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Felix Sunjoo Kim
- School of Chemical Engineering and Materials Science, Chung-Ang University (CAU), Seoul, 06974, Republic of Korea
| | - Bumjoon J Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
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Jia J, Wu F, Zhu L, Yang C. Unfused Electronic Acceptor-Based Polymers as Interfacial Materials for Efficient Inverted Perovskite Solar Cells. ACS Appl Mater Interfaces 2021; 13:33328-33334. [PMID: 34229426 DOI: 10.1021/acsami.1c09269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The interfacial issue resulting from surface trap states has become the crucial factor that limits the development of inverted perovskite solar cells (PSCs). Here, three unfused electronic acceptor-based polymers (PC-1-PC-3) with tailored alkyl groups were designed as interfacial materials to modify the interface contact between the perovskite active layer and electron transporting layer (ETL). Among them, PC-2 was found to extract interfacial charge faster and passivate trap states more efficiently. This leads to a remarkable increase in the short-circuit current density (22.49 mA cm-2) and fill factor (0.821), as well as a maximum power conversion efficiency of 20.50% with a negligible hysteresis, which is superior to the PC-1/PC-3 based devices and reference device with only the ETL. This study provides an insight for future molecular design of efficient interfacial materials for inverted PSCs.
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Affiliation(s)
- Jianchao Jia
- Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Fei Wu
- Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy, Faculty of Materials & Energy, Southwest University, Chongqing 400715, China
| | - Linna Zhu
- Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy, Faculty of Materials & Energy, Southwest University, Chongqing 400715, China
| | - Chuluo Yang
- Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
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Kwon NY, Park SH, Kang H, Kim YU, Chau HD, Harit AK, Woo HY, Yoon HJ, Cho MJ, Choi DH. Improved Stability of All-Polymer Solar Cells Using Crosslinkable Donor and Acceptor Polymers Bearing Vinyl Moieties in the Side-Chains. ACS Appl Mater Interfaces 2021; 13:16754-16765. [PMID: 33793188 DOI: 10.1021/acsami.1c00960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Crosslinkable polymers have attracted tremendous attention in various fields of science and technology, owing to their potential utilization in applications requiring dimensional and morphological stability under thermal and mechanical stress. In this study, random terpolymers were successfully synthesized by introducing thiophene-based monomers bearing vinyl functional groups in the side-chain of the polymer donor (PBDBT-BV20) and polymer acceptor (N2200-TV10) structures. The physical properties of the blend films of PBDBT-BV20 and N2200-TV10 before and after thermal crosslinking were extensively investigated and compared to those of the homogeneous individual polymer films. The results revealed that a network polymer with donor and acceptor polymer chains, which can lock the internal morphology, could be achieved by inducing crosslinking between the vinyl groups in the mixed state of PBDBT-BV20 and N2200-TV10. In addition, the power conversion efficiency (PCE) of the polymer solar cells (PSCs) containing the blend films that were crosslinked by a two-step thermal annealing process was improved. The enhanced PCE could be attributed to the individual crystallization of PBDBT-BV20 and N2200-TV10 in the blend phase at 120 °C and then thermal crosslinking at 140 °C. In addition, the PSCs with the crosslinked blend film exhibited an excellent shelf-life of over 1200 h and a thermally stable PCE. Furthermore, the crosslinked blend film exhibited excellent mechanical stability under bending stress in flexible PSCs using plastic substrates.
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Affiliation(s)
- Na Yeon Kwon
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Su Hong Park
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Hungu Kang
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Young Un Kim
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Hong Diem Chau
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Amit Kumar Harit
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Han Young Woo
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Hyo Jae Yoon
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Min Ju Cho
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Dong Hoon Choi
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
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Li Y, Meng H, Liu T, Xiao Y, Tang Z, Pang B, Li Y, Xiang Y, Zhang G, Lu X, Yu G, Yan H, Zhan C, Huang J, Yao J. 8.78% Efficient All-Polymer Solar Cells Enabled by Polymer Acceptors Based on a B←N Embedded Electron-Deficient Unit. Adv Mater 2019; 31:e1904585. [PMID: 31532877 DOI: 10.1002/adma.201904585] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/19/2019] [Indexed: 06/10/2023]
Abstract
In the field of all-polymer solar cells (all-PSCs), all efficient polymer acceptors that exhibit efficiencies beyond 8% are based on either imide or dicyanoethylene. To boost the development of this promising solar cell type, creating novel electron-deficient units to build high-performance polymer acceptors is critical. A novel electron-deficient unit containing B←N bonds, namely, BNIDT, is synthesized. Systematic investigation of BNIDT reveals desirable properties including good coplanarity, favorable single-crystal structure, narrowed bandgap and downshifted energy levels, and extended absorption profiles. By copolymerizing BNIDT with thiophene and 3,4-difluorothiophene, two novel conjugated polymers named BN-T and BN-2fT are developed, respectively. It is shown that these polymers possess wide absorption spectra covering 350-800 nm, low-lying energy levels, and ambipolar film-transistor characteristics. Using PBDB-T as the donor and BN-2fT as the acceptor, all-PSCs afford an encouraging efficiency of 8.78%, which is the highest for all-PSCs excluding the devices based on imide and dicyanoethylene-type acceptors. Considering that the structure of BNIDT is totally different from these classical units, this work opens up a new class of electron-deficient unit for constructing efficient polymer acceptors that can realize efficiencies beyond 8% for the first time.
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Affiliation(s)
- Yongchun Li
- College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences, Beijing, 100190, China
| | - Huifeng Meng
- College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences, Beijing, 100190, China
| | - Tao Liu
- Department of Chemistry and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration & Reconstruction, Hong Kong University of Science and Technology Clear Water Bay, Kowloon, Hong Kong
| | - Yiqun Xiao
- Department of Physics, The Chinese University of Hong Kong New Territories, Sha Tin, Hong Kong
| | - Zhonghai Tang
- Beijing National Laboratory for Molecular Sciences Organic Solids Laboratory, CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Bo Pang
- College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China
| | - Yuqing Li
- College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences, Beijing, 100190, China
| | - Ying Xiang
- College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China
| | - Guangye Zhang
- EFlexPV Limited, Longhua District, Shenzhen, 518000, China
| | - Xinhui Lu
- Department of Physics, The Chinese University of Hong Kong New Territories, Sha Tin, Hong Kong
| | - Gui Yu
- Beijing National Laboratory for Molecular Sciences Organic Solids Laboratory, CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - He Yan
- Department of Chemistry and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration & Reconstruction, Hong Kong University of Science and Technology Clear Water Bay, Kowloon, Hong Kong
| | - Chuanlang Zhan
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences, Beijing, 100190, China
| | - Jianhua Huang
- College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China
| | - Jiannian Yao
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences, Beijing, 100190, China
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Kim SW, Wang Y, You H, Lee W, Michinobu T, Kim BJ. Impact of Incorporating Nitrogen Atoms in Naphthalenediimide-Based Polymer Acceptors on the Charge Generation, Device Performance, and Stability of All-Polymer Solar Cells. ACS Appl Mater Interfaces 2019; 11:35896-35903. [PMID: 31532612 DOI: 10.1021/acsami.9b12037] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Substitution of C atoms in a polymer backbone by N atoms allows for the facile tuning of the energy levels as well as the backbone conformation and packing structures of conjugated polymers. Herein, we report a series of three polymer acceptors (PAs) with N atoms introduced at different positions of the backbone and investigate how these N atoms affect the device performances of all-polymer solar cells (all-PSCs). The three PAs, namely, P(NDI2DT-BTT), P(NDI2DT-PTT), and P(NDI2DT-BTTz), are composed of naphthalenediimide (NDI)-based and benzothiadiazole (BT)-based derivatives (dithiophene-BT (BTT), dithiophene-thiadiazolepyridine (PTT), and dithiazole-BT (BTTz)). The PTT and BTTz units are synthesized by replacing the C atoms in BT and thiophene, respectively, with N atoms, which effectively tune the optical, electrochemical, and charge-transporting properties of the corresponding PAs. The all-PSCs using poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl))benzo[1,2-b:4,5-b']dithiophene)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2-c:4,5-c']dithiophene-4,8-dione)] (PBDB-T) as a polymer donor and P(NDI2DT-PTT) as PA exhibit a significantly enhanced power conversion efficiency (PCE) of 6.95%, whereas the all-PSCs based on the other PAs show relatively lower PCEs (6.02% for PBDB-T:P(NDI2DT-BTT) and 1.43% for PBDB-T:P(NDI2DT-BTTz)). The high PCE of the PBDB-T:P(NDI2DT-PTT) device is due to the superior charge transfer and charge dissociation, resulting from the closely matched energy levels between PBDB-T and P(NDI2DT-PTT), as well as a more favorable bulk heterojunction morphology with improved miscibility. Importantly, the P(NDI2DT-PTT)-based all-PSC device shows improved air stability compared to the P(NDI2DT-BTT)-based device, which is most likely due to a decreased lowest unoccupied molecular orbital level of the PA. Our findings suggest that the incorporation of N atoms into the PAs is an effective strategy for improving the efficiency and stability of all-PSCs.
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Affiliation(s)
- Sang Woo Kim
- Department of Chemical and Biomolecular Engineering , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Republic of Korea
| | - Yang Wang
- Department of Materials Science and Engineering , Tokyo Institute of Technology , Tokyo 152-8552 , Japan
| | - Hoseon You
- Department of Chemical and Biomolecular Engineering , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Republic of Korea
| | - Wonho Lee
- Department of Polymer Science and Engineering , Kumoh National Institute of Technology , Gumi 39177 , Republic of Korea
| | - Tsuyoshi Michinobu
- Department of Materials Science and Engineering , Tokyo Institute of Technology , Tokyo 152-8552 , Japan
| | - Bumjoon J Kim
- Department of Chemical and Biomolecular Engineering , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Republic of Korea
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