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2. Mesoscopic 2D Charge Transport in Commonplace PEDOT:PSS Films

Author

Honma, Yuta, Itoh, Keisuke, Masunaga, Hiroyasu, Fujiwara, Akihiko, Nishizaki, Terukazu, Iguchi, Satoshi, and Sasaki, Takahiko

Subjects
Condensed Matter - Materials Science
Abstract

The correlation between the transport properties and structural degrees of freedom of conducting polymers is a central concern in both practical applications and scientific research. In this study, we demonstrated the existence of mesoscopic two-dimensional (2D) coherent charge transport in poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film by performing structural investigations and high-field magnetoconductance (MC) measurements in magnetic fields of up to 15 T. We succeeded in observing marked positive MCs reflecting 2D electronic states in a conventional drop-cast film. This low-dimensional feature is surprising, since PEDOT:PSS-a mixture of two different polymers-seems to be significantly different from crystalline 2D materials in the viewpoint of the structural inhomogeneity, especially in popular drop-cast thick films. The results of the structural experiments suggest that such 2D transport originates from the nanometer-scale self-assembled laminated structure, which is composed of PEDOT nanocrystals wrapped by insulating sheets consisting of amorphous PSSs. These results indicate that charge transport in the PEDOT:PSS film can be divided into two regimes: mesoscopic 2D coherent tunneling and macroscopic three-dimensional hopping among 2D states. Our findings elucidate the hieratical nature of charge transport in the PEDOT:PSS film, which could provide new insight into a recent engineering concern, i.e., the anisotropic conductance., Comment: 11 pages, 8 figures, accepted for publication in Adv. Electron. Mater

Published
2018
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6. 1000 spider silkomes: Linking sequences to silk physical properties

Author

Arakawa, Kazuharu, primary, Kono, Nobuaki, additional, Malay, Ali D., additional, Tateishi, Ayaka, additional, Ifuku, Nao, additional, Masunaga, Hiroyasu, additional, Sato, Ryota, additional, Tsuchiya, Kousuke, additional, Ohtoshi, Rintaro, additional, Pedrazzoli, Daniel, additional, Shinohara, Asaka, additional, Ito, Yusuke, additional, Nakamura, Hiroyuki, additional, Tanikawa, Akio, additional, Suzuki, Yuya, additional, Ichikawa, Takeaki, additional, Fujita, Shohei, additional, Fujiwara, Masayuki, additional, Tomita, Masaru, additional, Blamires, Sean J., additional, Chuah, Jo-Ann, additional, Craig, Hamish, additional, Foong, Choon P., additional, Greco, Gabriele, additional, Guan, Juan, additional, Holland, Chris, additional, Kaplan, David L., additional, Sudesh, Kumar, additional, Mandal, Biman B., additional, Norma-Rashid, Y., additional, Oktaviani, Nur A., additional, Preda, Rucsanda C., additional, Pugno, Nicola M., additional, Rajkhowa, Rangam, additional, Wang, Xiaoqin, additional, Yazawa, Kenjiro, additional, Zheng, Zhaozhu, additional, and Numata, Keiji, additional

Published
2022
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9. Formation of Clusters in Whiskies During the Maturation Process

Author

Morishima, Ken, Nakamura, Noriko, Matsui, Keisuke, Tanaka, Yoshikazu, Masunaga, Hiroyasu, Mori, Shoko, Iwashita, Takashi, li, Xiang, and Shibayama, Mitsuhiro

Subjects
whisky, Food Chemistry, maturation, small angle X‐ray scattering, Food Handling, Alcoholic Beverages, food and beverages, dynamic light scattering, Models, Theoretical, X-Ray Diffraction, Taste, Fermentation, Scattering, Small Angle, clusters, Food Analysis
Abstract

Maturation provides whisky with a mild and smooth texture by removing the irritating alcoholic flavor. However, the precise mechanism by which the whisky flavor is improved through the maturation process remains unknown. In this study, we performed mesoscopic structural measurements—dynamic light scattering (DLS) and small‐angle X‐ray scattering (SAXS)—to elucidate the relationship between the liquid structure and flavor maturation of whiskies. Both techniques detected two scattering components corresponding to the clusters formed by the extractives from oak casks during maturation, which are not present in the new make (freshly distilled whisky). Analyzing the scattering profiles revealed that only the small clusters increase in concentration during maturation. It is concluded the small cluster component is crucial for obtaining flavorful whiskies, while the large cluster component, whose concentration is independent of the maturation time, is related to the alcoholic irritation of the whiskies, as demonstrated by the sonication test.

Published
2018

11. Microstructure Investigation of Polymer Electrolyte Fuel Cell Catalyst Layers Containing Perfluorosulfonated Ionomer

Author

Koga, Maito, primary, Matsumoto, Hidetoshi, additional, Kunishima, Mitsunori, additional, Tokita, Masatoshi, additional, Masunaga, Hiroyasu, additional, Ohta, Noboru, additional, Takeuchi, Akihisa, additional, Mizukado, Junji, additional, Sugimori, Hidekazu, additional, Shinohara, Kazuhiko, additional, Uemura, Suguru, additional, Yoshida, Toshihiko, additional, and Hirai, Shuichiro, additional

Published
2021
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13. In-Situ X-Ray Analyses of Structural Change During Drawing and Shrinking of Linear Low-Density Polyethylene Film.

Author

Yoshizawa, Hiroaki, Takazawa, Ayaka, Kakiage, Masaki, Yamanobe, Takeshi, Hayashi, Naoki, Hiraoka, Maki, Masunaga, Hiroyasu, Aoyama, Kouki, and Uehara, Hiroki

Subjects
POLYETHYLENE films, SYNCHROTRON radiation sources, SMALL-angle X-ray scattering, X-rays, LOW density polyethylene, MOLECULAR orientation
Abstract

Structural changes during the drawing and shrinking of linear low-density polyethylene (LLDPE) film are analyzed through in-situ X-ray measurements. A synchrotron radiation source enables simultaneous analyses combining small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD). During drawing, the original unoriented SAXS and WAXD patterns transformed into line and spot patterns, indicating the orientation of both lamellar stacking and the molecular axis along the drawing direction. During the subsequent shrinking these patterns are retained, suggesting the tilted lamellar and molecular chains. A possible model for structural changes indicates that tie molecules between lamellae effectively transmit drawing and shrinking stresses, which contributes to desirable actuation properties. [ABSTRACT FROM AUTHOR]

Published
2022
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15. Bis(aminothiolato)nickel nanosheet as a redox switch for conductivity and an electrocatalyst for the hydrogen evolution reaction† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc02688a

Author

Sun, Xinsen, Wu, Kuo-Hui, Sakamoto, Ryota, Kusamoto, Tetsuro, Maeda, Hiroaki, Ni, Xiaojuan, Jiang, Wei, Liu, Feng, Sasaki, Sono, Masunaga, Hiroyasu, and Nishihara, Hiroshi

Subjects
Chemistry
Abstract

Precisely tuned functional coordination nanosheet exhibits competent catalytic activity for HER, accompany with drastic electronic property switching by redox treatment., A π-conjugated coordination nanosheet comprising bis(aminothiolato)nickel (NiAT) moieties was synthesized by the reaction of Ni(acac)2 with 1,3,5-triaminobenzene-2,4,6-trithiol at liquid–liquid and gas–liquid interfaces. The sheet thickness could be controlled down to a single layer (0.6 nm). Selected area electron diffraction and grazing incidence X-ray diffraction analyses indicated the formation of a flat crystalline sheet with a kagome lattice stacked in a staggered alignment. NiAT was reversibly interconverted to a bis(iminothiolato)nickel (NiIT) nanosheet by the chemical 2H+–2e– reaction, which was accompanied by a drastic change in electrical conductivity from 3 × 10–6 to 1 × 10–1 S cm–1. This change in conductivity was explained by the difference in band structures between NiAT and NiIT. NiAT acted as an efficient electrocatalyst for the hydrogen evolution reaction, showing strong acid durability and an onset overpotential of –0.15 V.

Published
2017

22. Relationship between morphological change and crystalline phase transitions of polyethylene-poly(ethylene oxide) diblock copolymers. 3. Dependence of morphological transition phenomena on the PE/PEO segmental lengths and its possible origins

Author

Weiyu Cao, Tashiro, Kohji, Masunaga, Hiroyasu, Sasaki, Sono, and Takata, Masaki

Subjects
Phase transformations (Statistical physics) -- Analysis, Polyethylene -- Structure, Polyethylene -- Chemical properties, Raman spectroscopy -- Usage, Proteins -- Structure, Proteins -- Analysis, Chemicals, plastics and rubber industries
Published
2009

23. Relationship between morphological change and crystalline phase transitions of polyethylene?poly(ethylene Oxide) diblock copolymers, revealed by the temperature-dependent synchrotron WAXD/SAXS and infrared/raman spectral measurements

Author

Weiyu, Cao, Tashiro, Kohji, Hanesaka, Makoto, Takeda, Shinichi, Masunaga, Hiroyasu, Sasaki, Sono, and Takata, Masaki

Subjects
Ethylene oxide -- Properties, Ethylene oxide -- Research, Phase transformations (Statistical physics) -- Research, Raman spectroscopy -- Usage, Infrared spectroscopy -- Usage, Chemicals, plastics and rubber industries
Published
2009

30. Characterization of Surface Microstructures on Bio-based Polymer Film Fabricated with Nano-imprint Lithography by Synchrotron Radiation Small Angle X-ray Scattering

Author

Shinohara, Takamichi, primary, Shirahase, Tomoko, additional, Murakami, Daiki, additional, Hoshino, Taiki, additional, Kikuchi, Moriya, additional, Koike, Jun-ichiro, additional, Horigome, Misao, additional, Masunaga, Hiroyasu, additional, Ogawa, Hiroki, additional, and Takahara, Atsushi, additional

Published
2011
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38. Structural evolution in the isothermal crystallization process of the molten nylon 10/10 traced by time-resolved infrared spectral measurements and synchrotron SAXS/WAXD measurements

Author

Tashiro, Kohji, primary, Nishiyama, Asami, additional, Tsuji, Sawako, additional, Hashida, Tomoko, additional, Hanesaka, Makoto, additional, Takeda, Shinichi, additional, Weiyu, Cao, additional, Reddy, Kummetha Raghunatha, additional, Masunaga, Hiroyasu, additional, Sasaki, Sono, additional, Ito, Kazuki, additional, and Takata, Masaki, additional

Published
2009
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45. Anomalous phase behavior in blends of -SO3H terminated polystyrene with poly(n-butyl acrylate) containing a small amount of tertiary amino groups.

Author

Yamamoto, Kenji, Nanakno, Ayumi, Masunaga, Hiroyasu, and Akiba, Isamu

Subjects
AMINO group, X-ray scattering, POLYSTYRENE, MICROSCOPY, DIMETHYLAMINOETHANOL, METHYL methacrylate, MISCIBILITY, HYDROGEN bonding, COPOLYMERS
Abstract

Phase behavior in the blend of -SO3H terminated polystyrene (PSS) with poly(n-butyl acrylate-co-N,N-dimethylaminoethyl methacrylate) containing 6.0 mol% N,N-dimethylaminoethyl methacrylate (P1) is investigated by optical microscopy and small-angle X-ray scattering (SAXS). Comparing the miscibility of polystyrene/P1 blend, it is confirmed that the miscibility of the PSS/P1 blend is drastically improved by the hydrogen bonds between -SO3H and tertiary amino group. In addition, two-phase region of the PSS/P1 blend is split into two regions around the stoichiometric composition, in which the molar ratio of -SO3H to tertiary amino group is 1:1 stoichiometry. SAXS result shows that the PSS/P1 blend at stoichiometric composition forms a block copolymer-like aggregate and it takes a disorder state. [ABSTRACT FROM AUTHOR]

Published
2008

47. Relationship between morphological change and crystalline phase transitions of polyethylene-poly(ethylene oxide) diblock copolymers. 3. Dependence of morphological transition phenomena on the PE/PEO segmental lengths and its possible origins.

Author

Cao W, Tashiro K, Masunaga H, Sasaki S, and Takata M

Abstract

By measurement of the small-angle and wide-angle X-ray scatterings and infrared and Raman spectra and thermal data, microphase separation phenomena have been investigated for a series of polyethylene-poly(ethylene oxide) diblock copolymer (PE-b-PEO) in both the heating and cooling processes and compared with the structural changes occurring inside the PE and PEO domains. The complicated morphological changes between lamella, perforated lamella, gyroid, cylinder, and sphere phases were detected for the copolymer with relatively short PE segments. The orthorhombic crystalline structure of PE was kept unchanged in the lamella-to-gyroid transition. When the PE orthorhombic phase transformed to the pseudohexagonal or rotator phase, the gyroid morphology changed to the cylinder. On the other hand, the diblock copolymer with relatively long PE segment was found to show only the lamellar morphology, in which the order-disorder structural transition between the orthorhombic and pseudohexagonal phases occurred in the PE crystal region. As a possibility, the large difference in morphological change between the copolymers with short and long PE segments has been ascribed to the difference in thermal mobility of PE segments, which is controlled by the conformation of chains and their packing mode, i.e., an extended chain or a folded chain. The extended chains may move thermally and actively along the interfacial boundary in addition to the librational motion around the chain axis, resulting in a variety of morphological changes, whereas the thermal motion of the folded chains may be suppressed because of the geometrical constraint and does not cause such a large-scale morphological change from the lamellar structure. This concept, a thermal activity and geometrical constraint, is considered to be quite important in the interpretation of complicated morphological changes observed for many crystalline-amorphous and crystalline-crystalline diblock copolymers when viewed from the molecular level.

Published
2009
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48. Relationship between morphological change and crystalline phase transitions of polyethylene-poly(ethylene oxide) diblock copolymers, revealed by the temperature-dependent synchrotron WAXD/SAXS and infrared/Raman spectral measurements.

Author

Weiyu C, Tashiro K, Hanesaka M, Takeda S, Masunaga H, Sasaki S, and Takata M

Abstract

The phase transition behaviors of low-molecular-weight polyethylene-poly(ethylene oxide) (PE-b-PEO) diblock copolymers with the monomeric units of PE/PEO = 17/40 and 39/86 have been successfully investigated through the temperature-dependent measurements of wide-angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS), infrared and Raman spectra, as well as thermal analysis. These diblock copolymers had been believed to show only order-to-disorder transition of lamellar morphology in a wide temperature region, but it has been found here for the first time that this copolymer clearly exhibits the three stages of transitions among lamella, gyroid, cylinder, and spherical phases in the heating and cooling processes. The WAXD and IR/Raman spectral measurements allowed us to relate these morphological changes to the microscopic changes in the aggregation states of PEO and PE segments. In the low-temperature region the PEO segments form the monoclinic crystal of (7/2) helical chain conformation and the PE segments of planar-zigzag form take the orthorhombic crystalline phase. These crystalline lamellae of PEO and PE segments are alternately stacked with the long period of 165 Angstroms. In a higher temperature region, where the PEO crystalline parts are on the way of melting but the PE parts are still in the orthorhombic phase, the gyroid morphology is detected in the SAXS data. By heating further, the gyroid morphology changes to the hexagonally packed cylindrical morphology, where the orthorhombic phase of PE segments is gradually disordered because of thermally activated molecular motion and finally transforms to the pseudohexagonal or rotator phase. Once the PE segments are perfectly melted, the higher-order structure changes from the cylinder to the spherical morphology. These morphological transitions might relate to the thermally activated motions of two short chain segments of the diblock copolymer, although the details of the transition mechanism are unclear at the present stage.

Published
2009
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