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171.
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173.
Zhi Jiang Kenjiro Fukuda Wenchao Huang Sungjun Park Roda Nur Md. Osman Goni Nayeem Kilho Yu Daishi Inoue Masahiko Saito Hiroki Kimura Tomoyuki Yokota Shinjiro Umezu Daisuke Hashizume Itaru Osaka Kazuo Takimiya Takao Someya 《Advanced functional materials》2019,29(6)
Flexible and stretchable organic photovoltaics (OPVs) are promising as a power source for wearable devices with multifunctions ranging from sensing to locomotion. Achieving mechanical robustness and high power conversion efficiency for ultraflexible OPVs is essential for their successful application. However, it is challenging to simultaneously achieve these features by the difficulty to maintain stable performance under a microscale bending radius. Ultraflexible OPVs are proposed by employing a novel metal‐oxide‐free cathode that consists of a printed ultrathin metallic transparent electrode and an organic electron transport layer to achieve high electron‐collecting capabilities and mechanical robustness. In fact, the proposed ultraflexible OPV achieves a power conversion efficiency of 9.7% and durability with 74% efficiency retention after 500 cycles of deformation at 37% compression through buckling. The proposed approach can be applied to active layers with different morphologies, thus suggesting its universality and potential for high‐performance ultraflexible OPV devices. 相似文献
174.
Hideto Tsuji Yoshiko Yamamura Tomoyuki Ono Takashi Saeki Hiroyuki Daimon Koichi Fujie 《大分子反应工程》2008,2(6):522-528
Aliphatic dicarboxylic acid/aliphatic diol‐derived polyesters, poly(butylene succinate) and poly(butylene succinate/adipate), have been hydrolytically degraded in the melt in high‐temperature and high‐pressure water over a wide temperature range of 180–300 °C for periods of up to 30 min. The formation/decomposition of succinic acid (SA), adipic acid (AA), and butane‐1,4‐diol (BD), plus the molecular weight change of PBS and PBSA were then investigated. SA and AA were recovered at maximum yields of 65–80%, whereas BD was recovered at a maximum yield of only 30%, probably because of its decomposition. The obtained results were compared with those reported for aliphatic hydroxycarboxylic acid‐derived polyesters and aromatic dicarboxylic acid/aliphatic diol‐derived polyesters.
175.
Wang GX Han GF Ye Q Xiong RG Akutagawa T Nakamura T Chan PW Huang SD 《Dalton transactions (Cambridge, England : 2003)》2008,(19):2527-2530
A homochiral rare-earth metal Tb complex that exhibited a very large dielectric anisotropic property with a temperature-independent feature is obtained. Our findings on high-dielectric anisotropy will provide a new impetus in this field of materials science. 相似文献
176.
Taichi Kusakabe Satoshi Takaishi Tomoyuki Mochida Tat'yana A. Peganova Oleg V. Gusev 《Tetrahedron》2008,64(2):319-327
Oxidative cyclization-carbonylation of 2-alkyl-2-propargylcyclohexane-1,3-diones mediated by Pd(TFA)2/2,2′-isopropylidenebis[(4R)-4-(3,4-dimethoxyphenyl)-2-oxazoline] 28 afforded bicyclic-β-alkoxyacrylates in 51-74% yields with 72-82% ee. The products containing quaternary carbon were converted to optically active hydrindanes 33. 相似文献
177.
Dr. Tomoyuki Ikai Sayaka Miyoshi Dr. Kosuke Oki Dr. Ranajit Saha Dr. Yuh Hijikata Prof. Eiji Yashima 《Angewandte Chemie (International ed. in English)》2023,62(20):e202301962
Fully π-conjugated ladder polymers with a spiral geometry represent a new class of helical polymers with great potential for organic nanodevices, but there is no precedent for an optically active helical ladder polymer totally composed of achiral units. We now report the defect-free synthesis and resolution of a fully π-conjugated helical ladder polymer with a rigid helical cavity, which has been achieved by quantitative and chemoselective acid-promoted alkyne benzannulations of a rationally designed, random-coil achiral polymer followed by chromatographic enantioseparation. Because of a sufficiently high helix-inversion barrier, the isolated excess one-handed helical ladder polymer with a degree of polymerization of more than 15 showed a strong circular dichroism with a dissymmetry factor of up to 1.7×10−2 and is thermally stable, maintaining its optical activity in solution even at 100 °C, as well-supported by molecular dynamics simulation. 相似文献
178.
Reduction of dibenzo[a,e]pentalene 3 (denoted as dibenzopentalene hereafter) with excess lithium gave dilithium dibenzopentalenide 1. Since oxidation of 1 with iodine gave 3, redox behavior between 1 and 3 is controllable and reversible. Reaction of 3 with methyllithium gave lithium 5-methyldibenzopentalenide 5, the formation of which was evidenced by some trapping experiments and X-ray crystallographic analysis. Reactions of 3 with halogens gave 5,10-dihalodibenzopentalenes, 8 and 9. Some optical properties of novel dibenzopentalene derivatives are also demonstrated. 相似文献
179.
Ueno K Juodkazis S Shibuya T Yokota Y Mizeikis V Sasaki K Misawa H 《Journal of the American Chemical Society》2008,130(22):6928-6929
We demonstrate the possibility to achieve optical triggering of photochemical reactions via two-photon absorption using incoherent light sources. This is accomplished by the use of arrays of gold nanoparticles, specially tailored with high precision to obtain high near-field intensity enhancement. 相似文献
180.
Sonomi Arata Dr. Yuna Kim Prof. Norihisa Hoshino Dr. Keishiro Tahara Dr. Kiyonori Takahashi Dr. Tomofumi Kadoya Tomonori Inoue Prof. Takayoshi Nakamura Prof. Tomoyuki Akutagawa Prof. Jun-ichi Yamada Prof. Kazuya Kubo 《欧洲无机化学杂志》2023,26(12):e202300017
Unsymmetrical gold(III)-dithiolene complexes are potential candidates for molecular materials that exhibit thermal structural phase transitions. In this study, unsymmetrical ppy-gold(III) (ppy−=C-deprotonated-2-phenylpyridine(−)) complexes [AuC5] and [AuC6] coordinated by dithiolene ligands containing tetrathiafulvalene (TTF) skeletons with pentylthio (2-{bis(pentylthio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate(2−)) and hexylthio groups (2-{bis(hexylthio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate(2−)) were synthesized. Both complexes exhibited a large absorption band at approximately 508 nm, owing to intramolecular ligand-to-ligand charge transfer. One-dimensional columnar structures with head-to-tail molecular arrangements around the metal ions were constructed in the crystals. The flexible alkylthio groups were intercalated into crystalline spaces between dithiolene ligands in the columns. [AuC5] exhibits a simple phase transition at 198 °C between crystalline and isotropic phases irreversibly. The crystalline phase of [AuC6] observed at 25 °C melted at 148 °C. Another crystalline phase grew above 148 °C with a very slow crystallization rate from the liquid phase and was completely transformed into an isotropic phase at 200 °C. 相似文献