- Development of a new conjugated polymer containing dialkoxynaphthalene for efficient polymer solar cells and organic thin film transistors
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A new semiconducting polymer, poly((5,5-E-α-((2-thienyl)methylene)-2- thiopheneacetonitrile)-alt-2,6-[(1,5-didecyloxy)naphthalene])) (PBTADN), an alternating copolymer of 2,3-bis-(thiophene-2-yl)-acrylronitrile and didecyloxy naphthalene, is synthesized and used as an active material for organic thin film transistors (OTFTs) and organic solar cells. The incorporation of 2,3-bis-(thiophene-2-yl)-acrylronitrile as an electron deficient group and didecyloxy naphthalene as an electron rich group resulted in a relatively low bandgap, high charge carrier mobility, and finally good photovoltaic performances of PBTADN solar cells. Because of the excellent miscibility of PBTADN and PC71BM, as confirmed by Grazing Incident X-ray Scattering (GIXS) measurements and Transmission Electron Microscopy (TEM), homogeneous film morphology was achieved. The maximum power conversion efficiency of the PBTADN:PC71BM solar cell reached 2.9% with a Voc of 0.88 V, a short circuit current density (Jsc) of 5.6 mA/cm2, and a fill factor of 59.1%. The solution processed thin film transistor with PBTADN revealed a highest saturation mobility of 0.025 cm2/Vs with an on/off ratio of 104. The molecular weight dependence of the morphology, charge carrier mobility, and finally the photovoltaic performances were also studied and it was found that high molecular weight PBTADN has better self assembly characteristics, showing enhanced performance.
- Kwon, Jun Ho,An, Ji-Young,Jang, Hanmae,Choi, Solji,Chung, Dae Sung,Lee, Min-Jung,Cha, Hyo-Jung,Park, Jin-Hee,Park, Chan-Eon,Kim, Yun-Hi
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- Visible-light-triggered molecular photoswitch based on reversible E/Z isomerization of a 1,2-dicyanoethene derivative
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A designed bis(dithienyl) dicyanoethene-based, strictly E/Z photoswitch (4TCE) operates through state-selective (E and Z isomer) photoactivation with visible light. The E and Z isomers of 4TCE exhibit remarkably different spectroscopic characteristics, including a large separation (70 nm) in their absorption maxima (λmax) and a 2.5-fold increase in molar extinction coefficient from cis to trans. The energetically stable trans form can be completely converted to the cis form within minutes when exposed to white light, whereas the reverse isomerization occurs readily upon irradiation by blue light (λ480 nm) or completely by thermal conversion at elevated temperatures. These features together with excellent thermal stability and photostability of both isomers make this new E/Z photoswitch a promising building block for photoswitchable materials that operate without the need for UV light.
- Guo, Xin,Zhou, Jiawang,Siegler, Maxime A.,Bragg, Arthur E.,Katz, Howard E.
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- Designing Nonfullerene Acceptors with Oligo(Ethylene Glycol) Side Chains: Unraveling the Origin of Increased Open-Circuit Voltage and Balanced Charge Carrier Mobilities
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Despite the recent rapid development of organic solar cells (OSCs), the low dielectric constant (?r=3–4) of organic semiconducting materials limits their performance lower than inorganic and perovskite solar cells. In this work, we introduce oligo(ethylene glycol) (OEG) side chains into the dicyanodistyrylbenzene-based non-fullerene acceptors (NIDCS) to increase its ?r up to 5.4. In particular, a NIDCS acceptor bearing two triethylene glycol chains (NIDCS-EO3) shows VOC as high as 1.12 V in an OSC device with a polymer donor PTB7, which is attributed to reduced exciton binding energy of the blend film. Also, the larger size grain formation with well-ordered stacking structure of the NIDCS-EO3 blend film leads to the increased charge mobility and thus to the improved charge mobility balance, resulting in higher JSC, FF, and PCE in the OSC device compared to those of a device using the hexyl chain-based NIDCS acceptor (NIDCS-HO). Finally, we fabricate NIDCS-EO3 devices with various commercial donors including P3HT, DTS-F, and PCE11 to show higher photovoltaic performance than the NIDCS-HO devices, suggesting versatility of NIDCS-EO3.
- Cui, Junjie,Park, Jung-Hwa,Kim, Dong Won,Choi, Min-Woo,Chung, Hae Yeon,Kwon, Oh Kyu,Kwon, Ji Eon,Park, Soo Young
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supporting information
p. 2481 - 2488
(2021/07/26)
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- Irradiation-Wavelength Directing Circularly Polarized Luminescence in Self-Organized Helical Superstructures Enabled by Hydrogen-Bonded Chiral Fluorescent Molecular Switches
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Two light-driven chiral fluorescent molecular switches, (R,S,R)-switch 1 and (R,S,R)-switch 2, are prepared by means of hydrogen-bonded (H-bonded) assembly of a photoresponsive (S) chiral fluorescent molecule, respectively with a cyano substitution at different positions as an H-bond acceptor and an opposite (R) chiral molecule as an H-bond donor. The resulting two switches exhibit tunable and reversible Z/E photoisomerization irradiated with 450 nm blue and 365 nm UV light. When doped into an achiral liquid crystal, both switches are found to be able to form a CPL tunable luminescent helical superstructure. In contrast to the tunable CPL characteristics of the system incorporating switch 2, exposure of the system incorporating switch 1 to 365 nm and 450 nm radiation can lead to controllable different photostationary CPL behavior, including switching-off and polarization inversion. In addition, optical information coding is demonstrated using the system containing switch 1.
- He, Yanrong,Zhang, Shu,Bisoyi, Hari Krishna,Qiao, Jinghui,Chen, Hong,Gao, JingJing,Guo, Jinbao,Li, Quan
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supporting information
p. 27158 - 27163
(2021/10/25)
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- NOVEL THIOPHENE COMPOUNDS, PROCESS FOR SYNTHESIS AND USE THEREOF
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The present invention relates to novel thiophene compounds of general Formula I, and their stereoisomers (diastereoisomers, enantiomers), pure or mixed, racemic mixtures, geometrical isomers, tautomers, pharmaceutically acceptable salts, hydrates, solvate
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Paragraph 0053; 0055
(2019/03/17)
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- Small-molecule semiconductors containing dithienylacrylonitrile for high-performance organic field-effect transistors
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We designed and synthesized four donor-acceptor-type conjugated small-molecule compounds DPP-CN-DTE-1, DPP-CN-DTE-2, DPP-DTE-CN-1 and DPP-DTE-CN-2. The four compounds contained long alkyl side chains on the diketopyrrolopyrrole acceptor unit and cyano (CN) groups substituted on the dithiophene ethylene donor unit at different positions. The four small molecules exhibited good thermal stability and solution dispersibility. The bottom gate-bottom contact OFET devices based on these compounds showed excellent p-type performances. The relationship between molecular structures and field-effect performances indicated that the alkyl side-chain length and the CN substituted position significantly affected their charge carrier transport properties. The DPP-CN-DTE-1 with side-chain 2-mercaptotetradecyl side-chains and inner-side substituted CN groups exhibited the highest hole mobility of 2.52 cm2 V-1 s-1. This work provided a promising approach to develop excellent p-type small-molecule semiconductors with high performance, good solution processability and thermal stability for device fabrications.
- Li, Dizao,Zou, Jiabin,Wei, Congyuan,Zhou, Yankai,Wang, Liping,Zhang, Weifeng,Yu, Gui
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p. 11457 - 11464
(2019/10/02)
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- Synthesis and properties of copolymers composed of arylenevinylene and phenothiazine for organic solar cells
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A series of new organic semiconducting copolymers composed of {(2E,2′E)-3,3′-[2,5-bis(octyloxy)-1,4-phenylene]-bis[2-(thiophen-2- yl)acrylonitrile]}(OPTAN) and 10(2′-ethylhexylphenothiazine) (PTZ) monomers, (the copolymers are hereafter referred to as pol
- Kim, Ji-Hoon,Mi, Dongbo,Kang, In-Nam,Shin, Won Suk,Yoon, Sung Cheol,Moon, Sang-Jin,Lee, Changjin,Lee, Jin-Kyun,Hwang, Do-Hoon
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experimental part
p. 5876 - 5882
(2012/06/04)
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- Synthesis, characterization, and electroluminescence of new conjugated polyfluorene derivatives containing various dyes as comonomers
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Four new fluorene-based alternating polymers (PFR1-S, PFR2-S, PFR3-S, and PFR4-S) containing different comonomers (R1, R2, R3, and R4) have been designed, synthesized, and characterized. These polymers were found to be thermally stable and readily soluble
- Cho, Nam Sung,Hwang, Do-Hopn,Jung, Byung-Jun,Lim, Eunhee,Lee, Jaemin,Shim, Hong-Ku
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p. 5265 - 5273
(2007/10/03)
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