KEIO RESEARCHERS INFORMATION SYSTEM

Books 【 Display / hide 】

Books 【 Display / hide 】

• Handbook of Porphrin Science

  HASOBE Taku, World Scientific Publishing Co. Pte. Ltd., 2014

  Scope: Supramolecular Assemblies of Porphyrins and Phthalocyanines Derivatives for Solar Energy conversion and Molecular Electronics

• 高次π空間の創発と機能開発

  HASOBE Taku, ＣＭＣ出版, 2013.03

  Scope: 158-165

• Handbook for Carbon Nanomaterials

  HASOBE Taku, 2012.06

  Scope: 95-130

• Energy and Electron Transfer Processes in Multiporphyrin Arrays

  HASOBE Taku, 2012.03

  Scope: 499-536

• 光化学 Vol. 41, No. 3, 157-159 (2010)

  羽曾部　卓・酒井　隼人, 光科学協会, 2010.12

  Scope: 157-159

Papers 【 Display / hide 】

Papers 【 Display / hide 】

• A Pentacene-based Nanotube Displaying Enriched Electrochemical and Photochemical Activities

  Kuroda K., Yazaki K., Tanaka Y., Akita M., Sakai H., Hasobe T., Tkachenko N., Yoshizawa M.

  Angewandte Chemie - International Edition (Angewandte Chemie - International Edition)  58 ( 4 ) 1115 - 1119 2019.01

  ISSN  14337851

  　View Summary

  © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Unlike previously well-studied, acyclic pentacene oligomers, the first synthesis of a cyclic pentacene trimer with a fixed tubular conformation is reported. A short-step synthesis starting from common pentacenequinone yielded the target molecule with a 1.5 nanometer length and a subnanometer pore. Steady-state spectroscopic analyses revealed that the close proximity of the non-conjugated, three pentacene chromophores allows the nanotube to display stepwise electrochemical/chemical oxidation characteristics. Furthermore, time-resolved transient absorption measurements elucidated the generation of an excited triplet state of the nanotube, with high quantum yield reaching about 180 % through intramolecular singlet fission and a very long triplet lifetime.

  • Access to Document (DOI)

• Quantitative Sequential Photoenergy Conversion Process from Singlet Fission to Intermolecular Two-Electron Transfers Utilizing Tetracene Dimer

  Nakamura S., Sakai H., Nagashima H., Kobori Y., Tkachenko N., Hasobe T.

  ACS Energy Letters (ACS Energy Letters)  4 ( 1 ) 26 - 31 2019.01

  　View Summary

  © 2018 American Chemical Society. Singlet fission (SF) theoretically enables the performance of the sequential photoenergy conversion process starting from the singlet state and leading to electron transfer (ET) with the radical ion pair quantum yield approaching 200%. Additionally, the long lifetime of the triplet state opens the possibility for an intermolecular ET process in a diffusion-limited reaction. However, the quantitative two-electron transfer process through SF has yet to be reported. Herein we demonstrate the quantitative sequential process involving SF and leading to intermolecular two-electron transfers using 2,2′-biphenyl-bridged tetracene dimer (Tet-BP-Tet: SF and electron donor) and chloranil (Ch: electron acceptor). The high-yield and long-lived individual triplet excited states of Tet-BP-Tet by SF (φ T = 175 ± 5% and τ T = 0.29 ms) resulted in the quantitative two-electron transfer process (φ ET = 173 ± 5%) with Ch in benzonitrile.

  • Access to Document (DOI)

• High-Yield Generation of Triplet Excited States by an Efficient Sequential Photoinduced Process from Energy Transfer to Singlet Fission in Pentacene-Modified CdSe/ZnS Quantum Dots

  Sakai H., Inaya R., Tkachenko N., Hasobe T.

  Chemistry - A European Journal (Chemistry - A European Journal)  24 ( 64 ) 17062 - 17071 2018.11

  ISSN  09476539

  　View Summary

  © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Singlet fission (SF) is expected to improve photoenergy conversion systems by generating two electrons from one photon. Pentacenes meet the energy-level matching condition between a singlet and two triplet states: [E(S1)≥2E(T1)]. However, the molar absorption coefficients of pentacenes in the approximately 400–500 nm region are limited, whereas quantum dots, such as CdSe/ZnS (QD), possess high fluorescence quantum yields and particle-size-dependent fluorescence wavelengths. Thus, a combination of QD (D) and pentacene (A) provides a system of both an enhanced light-harvesting efficiency throughout the solar spectrum and an efficient conversion of the harvested light into the triplet states by SF. Based on these points, m-phenylene-bridged triisopropylsilane (TIPS)-pentacene dimer-functionalized QD (denoted as m-(Pc)2-QD) was synthesized to examine the sequential photoinduced process from energy transfer to SF. In femtosecond transient absorption measurements, initial energy transfer from QD to pentacene (quantum yield: 87 %) and subsequent SF were efficiently observed. The quantum yield of triplet states of pentacene units (ΦΤ) based on the excitation of QD attained is 160±6.7 %.

  • Access to Document (DOI)

• Significant Enhancement of Absorption and Luminescence Dissymmetry Factors in the Far-Red Region: A Zinc(II) Homoleptic Helicate Formed by a Pair of Achiral Dipyrromethene Ligands

  Ito H., Sakai H., Okayasu Y., Yuasa J., Mori T., Hasobe T.

  Chemistry - A European Journal (Chemistry - A European Journal)  24 ( 63 ) 16889 - 16894 2018.11

  ISSN  09476539

  　View Summary

  © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim A homoleptic zinc(II) helicate organized by a pair of achiral dipyrromethene ligands through zinc(II) coordination was synthesized to evaluate the chiroptical properties. This zinc complex showed strong exciton-coupled chiroptical responses from the helical configuration with a large absorption dissymmetry factor |gabs| (up to 0.20). More importantly, intense polarized luminescence in the far-red region (700–850 nm) with a fluorescence quantum yield ΦFL of 0.23 was observed for this helicate with a dissymmetry factor |glum| of 0.022, the largest value among rare-earth- and precious-metal-free small molecules. These unprecedentedly large g values were supported by theoretical calculations.

  • Access to Document (DOI)

• Inter- and Intramolecular Electron-Transfer Reduction Properties of Coronenediimide Derivatives via Photoinduced Processes

  Yoshida M., Sakai H., Ohkubo K., Fukuzumi S., Hasobe T.

  Journal of Physical Chemistry C (Journal of Physical Chemistry C)  122 ( 25 ) 13333 - 13346 2018.06

  ISSN  19327447

  　View Summary

  Copyright © 2017 American Chemical Society. Coronenediimide derivatives with five- or six-membered maleimide groups [denoted as Cor(5Im)2 and Cor(6Im)2] were employed as electron acceptors to examine the electron-transfer reduction properties through photochemical and electrochemical measurements. In steady-state absorption and fluorescence measurements, the spectra of Cor(5Im)2 and Cor(6Im)2 became remarkably broadened and red-shifted as compared to pristine coronene (Cor). These results are supported by electrochemical measurements and DFT calculations. The rate constants of photoinduced intermolecular electron transfer from various donor molecules to 3Cor(5Im)2∗ or 3Cor(6Im)2∗ are determined by nanosecond transient absorption measurements. Although the back-electron-transfer reactions examined in this study proceed with the diffusion-limited rate constant in benzonitrile (PhCN), the rate constants of forward electron-transfer reactions (ket) increase with an increase in the driving force of electron transfer (-ΔGet) to approach the diffusion-limited rate constant. When the driving force dependence of ket was fit on the basis of the Marcus theory of electron transfer, the reorganization energy (λ) of the electron-transfer reduction of Cor(5Im)2 and Cor(6Im)2 are determined to be 0.77 and 1.15 eV, respectively. A new covalently perylene-linked donor-acceptor dyad was also synthesized to investigate the dynamics of ultrafast photoinduced intramolecular electron transfer.

  • Access to Document (DOI)

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Papers, etc., Registered in KOARA 【 Display / hide 】

Papers, etc., Registered in KOARA 【 Display / hide 】

• New progress in multi-exciton generation reactions using organic materials

  Hasobe, Taku

  科学研究費補助金研究成果報告書 2021

• Paradigm shift for observation of phosphorescence-derived circularly polarized luminescence in the near infrared region

  Hasobe, Taku

  科学研究費補助金研究成果報告書 2021

• Synthesis of amphipathic pentacenes for solar energy conversion

  Hasobe, Taku

  学事振興資金研究成果実績報告書 (慶應義塾大学)  2017

• Construction of aggregation-induced solar energy conversion systems

  Hasobe, Taku

  科学研究費補助金研究成果報告書 2017

• Construction of novel supramolecular nanoarrays for photocatalytic applications

  Hasobe, Taku

  科学研究費補助金研究成果報告書 2016

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Presentations 【 Display / hide 】

Presentations 【 Display / hide 】

• Control of Excite-State Dynamics and Optical Applications of Functional Supramolecular Architectures

  HASOBE Taku

  University Research Semina (University of Potsdam) , 

  2016.11

  , 

  Oral presentation (invited, special)

• Control of Excite-State Dynamics of Functional Supramolecular Architectures for Optical Applications

  HASOBE Taku

  TUT University Seminar (Tampere University of Technology) , 

  2016.11

  , 

  Oral presentation (invited, special)

• 有機低分子材料のナノ・メゾスケール構造体における励起状態ダイナミクス制御と応用

  HASOBE Taku

  高分子学会　印刷・情報記録・表示研究会および光反応・電子用材料研究会 (東京理科大学　森戸記念館　第1フォーラム) , 

  2016.10

  , 

  Oral presentation (invited, special)

• π共役分子および集積体の励起状態制御と機能性有機-無機複合材料への展開

  HASOBE Taku

  第49回π造形コロキウム, 

  2016.09

  , 

  Oral presentation (invited, special)

• π共役系分子集積体の励起状態ダイナミクス制御と機能発現

  HASOBE Taku

  九州地区高分子若手研究会・夏の講演会, 

  2016.07

  , 

  高分子若手研究会

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

Research Projects of Competitive Funds, etc. 【 Display / hide 】

• 材料合成を基盤とした多励起子生成ダイナミクスの新展開

  2024.04

  -

  2027.03

  基盤研究(B), Principal investigator

• Photofunctional Science of Meso-Hierarchy

  2023.04

  -

  2028.03

  学術変革領域研究(A), Principal investigator

• 水圏機能材料の励起ダイナミクス制御

  2022.04

  -

  2024.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, 新学術領域研究（研究領域提案型）, Principal investigator

• 一重項分裂における動的エキシトン解析

  2021.09

  -

  2023.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, 学術変革領域研究(A), Principal investigator

• 表面プラズモン効果との融合による一重項分裂のパラダイムシフト

  2021.07

  -

  2023.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Challenging Research (Exploratory), Principal investigator

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Intellectual Property Rights, etc. 【 Display / hide 】

Intellectual Property Rights, etc. 【 Display / hide 】

• 内包フラーレンを用いた光電変換装置

  Date applied： P2013-200603  2013.09 

  Date announced： P2015-69731A  2015.04 

  Patent, Joint

Awards 【 Display / hide 】

Awards 【 Display / hide 】

• JPP/SPP Young Invetigator Awards

  Taku Hasobe, 2014.06, Society of Porphyrins and Phthalocyanines

  Type of Award： International academic award (Japan or overseas)

• SPP/JPP Young Investigator Awards

  2014.06, Society of Porphyrins and Phthalocyanines

• The Young Scientists’ Prize, The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology

  HASOBE Taku, 2010.04, 文部科学省, 光電変換機能を有する分子集合体の創製と応用についての研究

  Type of Award： Other

  　View Description

  　近年、半導体材料としての利用に大きな期待が高まる有機色素材料は主に真空蒸着やスピンコートといったトップダウン的な薄膜作製法により分子組織化・成膜される。これらトップダウン法の問題点として、分子レベルでの精密な化学結合制御による組織化が困難であることが挙げられる。羽曾部卓氏は超分子的手法の基盤である化学結合制御に基づいた分子組織化に着目し、光電変換機能（光吸収・電荷分離・キャリア移動）を有する分子集合体という新規概念の提唱と創製を行った。実際の特性評価では光電変換効率が最高2%程度まで達し、非組織体と比較して最高50倍という大幅な改善が達成され、同氏の戦略の有用性を定量的に明らかにした。本研究成果は有機材料を用いた次世代の太陽電池など有機エレクトロニクス分野全般への応用が期待される。

Courses Taught 【 Display / hide 】

Courses Taught 【 Display / hide 】

• SEMINAR IN CHEMISTRY

  2024

• LABORATORIES IN CHEMISTRY 1

  2024

• INDEPENDENT STUDY ON FUNDAMENTAL SCIENCE AND TECHNOLOGY

  2024

• GRADUATE RESEARCH ON FUNDAMENTAL SCIENCE AND TECHNOLOGY 2

  2024

• GRADUATE RESEARCH ON FUNDAMENTAL SCIENCE AND TECHNOLOGY 1

  2024

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Committee Experiences 【 Display / hide 】

Committee Experiences 【 Display / hide 】

• 2015.04

  -

  2017.03

  関東支部常任幹事, 日本化学会

• 2015.04

  -

  2017.03

  日本化学会代議員, 日本化学会