ITARU OSAKA
Last Updated :2025/12/02
- Affiliations, Positions
- Graduate School of Advanced Science and Engineering, Professor
- Web Site
- E-mail
- iosaka
hiroshima-u.ac.jp
- Self-introduction
- My research interest includes molecular design and synthesis of functional conjugated polymers, self-assembly, and printable organic thin-film devices such as field-effect transistors and solar cells.
Basic Information
Major Professional Backgrounds
- 2006/02, 2009/03, Carnegie Mellon University, Department of Chemistry, Postdoctoral Researcher
- 2009/04/01, 2013/03/31, Hiroshima University, Graduate School of Engineering, Assistant Professor
- 2013/04, 2016/09, Institute of Physical and Chemical Research
- 2016/10/01, 2020/03/31, Hiroshima University, Institute of Engineering, Professor
- 2002/04, 2006/01, Fujifilm, Research Scientist
Educational Backgrounds
- University of Tsukuba, Japan, 1993/04, 1997/03
- University of Tsukuba, Japan, 1997/04, 2002/03
Academic Degrees
- Ph. D, University of Tsukuba
Educational Activity
- [Bachelor Degree Program] School of Engineering : Cluster 3(Applied Chemistry, Biotechnology and Chemical Engineering) : Program of Applied Chemistry
- [Master's Program] Graduate School of Advanced Science and Engineering : Division of Advanced Science and Engineering : Applied Chemistry Program
- [Master's Program] Graduate School of Advanced Science and Engineering : Division of Advanced Science and Engineering : Smart Innovation Program
- [Doctoral Program] Graduate School of Advanced Science and Engineering : Division of Advanced Science and Engineering : Applied Chemistry Program
- [Doctoral Program] Graduate School of Advanced Science and Engineering : Division of Advanced Science and Engineering : Smart Innovation Program
Research Fields
- Chemistry;Materials chemistry;Organic and hybrid materials
- Chemistry;Materials chemistry;Polymer / Textile materials
- Chemistry;Applied chemistry;Energy-related chemistry
- Chemistry;Materials chemistry;Device related chemistry
Research Keywords
- Organic functional materials
Conjugated polymers
Next generation photovoltaics
Printed electronics
Affiliated Academic Societies
- The Chemical Society of Japan, The Society of Polymer Science Japan, Japan Society of Applied Physics, The Society of Photopolymer Science and Technology, American Chemical Society, Materials Research Society
Educational Activity
Course in Charge
- 2025, Liberal Arts Education Program1, 1Term, Carbon-neutral Science and Technology
- 2025, Undergraduate Education, 4Term, Basic Organic Chemistry II
- 2025, Undergraduate Education, 2Term, Introduction to Fundamental Industry
- 2025, Undergraduate Education, 3Term, Synthetic Polymer Chemistry
- 2025, Undergraduate Education, Year, Graduation Thesis
- 2025, Graduate Education (Master's Program) , 1Term, Special Exercises on Applied Chemistry A
- 2025, Graduate Education (Master's Program) , 2Term, Special Exercises on Applied Chemistry A
- 2025, Graduate Education (Master's Program) , 3Term, Special Exercises on Applied Chemistry B
- 2025, Graduate Education (Master's Program) , 4Term, Special Exercises on Applied Chemistry B
- 2025, Graduate Education (Master's Program) , Year, Special Study on Applied Chemistry
- 2025, Graduate Education (Master's Program) , 3Term, Advanced Synthetic Polymer Chemistry
- 2025, Graduate Education (Doctoral Program) , Year, Special Study on Applied Chemistry
- 2025, Graduate Education (Master's Program) , 1Term, Sustainability Materials Science
Research Activities
Academic Papers
- Drastic effect of alkylation position in structurally simple benzobisthiazole-terthiophene copolymers on the performance of nonfullerene organic photovoltaics, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 98(8), 202508
- Dithienobenzimidazole-based semiconducting polymer for nonfullerene organic photovoltaics, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 98(3), 20250305
- Synthesis of indano[60]fullerene thioketone and its application in organic solar cells, BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY, 20, 1270-1277, 20240104
- Controlling the Thermoelectric Performance of Doped Naphthobisthiadiazole-Based Donor-Acceptor Conjugated Polymers through Backbone Engineering, ADVANCED SCIENCE, 11(48), 202412
- ★, Dithienonaphthobisthiadiazole synthesized by thienannulation of electron-deficient rings: an acceptor building unit for high-performance pi-conjugated polymers, CHEMICAL SCIENCE, 15(47), 19991-20001, 20241204
- A highly crystalline face-on pi-conjugated polymer based on alkoxythiophene-flanked benzobisthiazole for organic photovoltaics, POLYMER JOURNAL, 56(11), 1051-1059, 202411
- Photon energy loss in ternary polymer solar cells based on nonfullerene acceptor as a third component, BATTERY ENERGY, 3(5), 202409
- ★, Efficient Derivatization of a Thienobenzobisthiazole-Based pi-Conjugated Polymer Through Late-Stage Functionalization Towards High-Efficiency Organic Photovoltaic Cells, ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 63(47), 20241118
- Twisted diphenoquinones fused with thiophene rings: thiophene analogs of bianthrone, CHEMICAL COMMUNICATIONS, 60(75), 10410-10413, 20240916
- Manipulating the functionality and structures of pi-conjugated polymers utilizing intramolecular noncovalent interactions towards efficient organic photovoltaics, CHEMICAL SCIENCE, 15(17), 6349-6362, 20240501
- Two Isomeric Benzo[d]imidazole-Based Nonfullerene Acceptors for Organic Photovoltaics, ACS APPLIED ENERGY MATERIALS, 7(7), 2946-2954, 20240323
- Bending the Rule: Naphthobisthiadiazole-Based Terpolymers with Both High Solubility and Crystallinity for Organic Photovoltaics, ACS APPLIED POLYMER MATERIALS, 6(5), 2586-2593, 20240221
- Dependence of Exciton Binding Energy on Bandgap of Organic Semiconductors, JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 14(50), 11412-11420, 20231211
- Simple pi-Conjugated Polymers Based on Bithiazole for Nonfullerene Organic Photovoltaics, ACS APPLIED MATERIALS & INTERFACES, 16(3), 3735-3743, 20240109
- Employment of Alkoxy Sidechains in Semicrystalline Semiconducting Polymers for Ambient-Stable p-Doped Conjugated Polymers, MACROMOLECULES, 57(1), 328-338, 20231214
- Ordered p-conjugated polymer backbone in amorphous blend for high efficiency nonfullerene organic photovoltaics, COMMUNICATIONS MATERIALS, 4(1), 20230921
- Microscopic Mechanism of High Efficiency and Stability of Inverted Polymer Fullerene Solar Cells, ACS APPLIED ENERGY MATERIALS, 6(11), 6299-6310, 20230519
- Interplay Between pi-Conjugated Polymer Donors and Acceptors Determines Crystalline Order of Their Blends and Photovoltaic Performance, ADVANCED ENERGY MATERIALS, 13(13), 202304
- Exciton dynamics of a fused ring pi-conjugated nonfullerene molecule based on dithienonaphthobisthiadiazole, JAPANESE JOURNAL OF APPLIED PHYSICS, 62(SK), 20230801
- Naphthobispyrazine bisimide-based semiconducting polymers as electron acceptors for all-polymer photovoltaic cells, POLYMER JOURNAL, 55(4), 443-450, 202304
- Halogen-Free p-Conjugated Polymers Based on Thienobenzobisthiazole for Efficient Nonfullerene Organic Solar Cells: Rational Design for Achieving High Backbone Order and High Solubility, ADVANCED SCIENCE, 10(5), 202302
- Effect of UV-Light Irradiation on Charge-Accumulation States in PTzBT Polymer Solar Cells, JOURNAL OF PHOTOPOLYMER SCIENCE AND TECHNOLOGY, 35(3), 193-197, 2022
- Synergetic Effect on Enhanced Photovoltaic Performance of Spray-Coated Perovskite Solar Cells Enabled by Additive Doping and Antisolvent Additive Spraying Treatment, ACS APPLIED ENERGY MATERIALS, 5(4), 4149-4158, 20220425
- Ester-functionalized quinoxaline-based polymers for application in organic photovoltaics, MATERIALS CHEMISTRY AND PHYSICS, 287, 20220801
- Tunable Photoelectric Properties of n-Type Semiconducting Polymer:Small Molecule Blends for Red Light Sensing Phototransistors, ADVANCED OPTICAL MATERIALS, 10(10), 202205
- Stability improvement mechanism due to less charge accumulation in ternary polymer solar cells, NPJ FLEXIBLE ELECTRONICS, 6(1), 20220420
- Naphthobisthiadiazole-Based pi-Conjugated Polymers for Nonfullerene Solar Cells: Suppressing Intermolecular Interaction Improves Photovoltaic Performance, ACS APPLIED MATERIALS & INTERFACES, 14(12), 14400-14409, 20220330
- Naphthobispyrazine Bisimide: A Strong Acceptor Unit for Conjugated Polymers Enabling Highly Coplanar Backbone, Short pi - pi Stacking, and High Electron Transport, CHEMISTRY OF MATERIALS, 34(6), 2717-2729, 20220322
- Preparation of (pin)B-B(dan), ORGANIC SYNTHESES, 95, 218-+, 2018
- Analyses of Charge Accumulation of PTzBT Ternary Polymer Solar Cells Using ESR Spectroscopy, JOURNAL OF PHOTOPOLYMER SCIENCE AND TECHNOLOGY, 34(4), 351-356, 2021
- Solution Processable Pentafluorophenyl End-Capped Dithienothiophene Organic Semiconductors for Hole-Transporting Organic Field Effect Transistors, ADVANCED ELECTRONIC MATERIALS, 8(3), 202203
- Dithiazolylthienothiophene Bisimide: A Novel Electron-Deficient Building Unit for N-Type Semiconducting Polymers, ACS APPLIED MATERIALS & INTERFACES, 11(26), 23410-23416, 20190604
- Dithienyl Acenedithiophenediones as New -Extended Quinoidal Cores: Synthesis and Properties, CHEMISTRY-A EUROPEAN JOURNAL, 23(19), 4579-4589, 20170403
- Synthesis and Characterization of an Alkoxythiazole-thiazolothiazole Semiconducting Polymer for Organic Solar Cells, ELECTROCHEMISTRY, 85(5), 266-271, 2017
- ★, Naphthobischalcogenadiazole Conjugated Polymers: Emerging Materials for Organic Electronics, ADVANCED MATERIALS, 29(25), 1605218, 20170705
- Naphthobispyrazine as an Electron-deficient Building Unit for pi-Conjugated Polymers: Efficient Synthesis and Polymer Properties, CHEMISTRY LETTERS, 46(8), 1193-1196, 20170530
- Stretchable and waterproof elastomer-coated organic photovoltaics for washable electronic textile applications, NATURE ENERGY, 2(10), 20170918
- Impact of side chain placement on thermal stability of solar cells in thiophene-thiazolothiazole polymers, JOURNAL OF MATERIALS CHEMISTRY C, 6(14), 3668-3674, 20180414
- ★, Advances in molecular design and synthesis of regioregular polythiophenes, ACCOUNTS OF CHEMICAL RESEARCH, 41(9), 1202-1214, 2008
- ★, Efficient inverted polymer solar cells employing favourable molecular orientation, NATURE PHOTONICS, 9(6), 403, 2015
- ★, High-efficiency polymer solar cells with small photon energy loss, NATURE COMMUNICATIONS, 6, 10085, 2015
- Copper-catalyzed Borylation of Bromoaryl Triflates with Diborons: Chemoselective Replacement of an Ar-Br Bond, CHEMISTRY LETTERS, 47(8), 957-959, 20180609
- Nickel and Nucleophilic Cobalt-Catalyzed Trideuteriomethylation of Aryl Halides Using Trideuteriomethyl p-Toluenesulfonate, ORGANIC LETTERS, 20(14), 4375-4378, 20180720
- Bimolecular recombination and fill factor in crystalline polymer solar cells, JAPANESE JOURNAL OF APPLIED PHYSICS, 57(8S3), 20080606
- Anthranilamide (aam)-substituted diboron: palladium-catalyzed selective B(aam) transfer, CHEMICAL COMMUNICATIONS, 54(67), 9290-9293, 20180828
- Correlation between Distribution of Polymer Orientation and Cell Structure in Organic Photovoltaics, ACS APPLIED MATERIALS & INTERFACES, 10(38), 32420-32425, 20180917
- Scalable Ultrasonic Spray-Processing Technique for Manufacturing Large-Area CH3NH3PbI3 Perovskite Solar Cells, ACS APPLIED MATERIALS & INTERFACES, 10(44), 38042-38050, 20181107
- Durable Ultraflexible Organic Photovoltaics with Novel Metal-Oxide-Free Cathode, ADVANCED FUNCTIONAL MATERIALS, 29(6), 201902
- Anthranilamide (aam)-substituted arylboranes in direct carbon-carbon bond-forming reactions, CHEMICAL COMMUNICATIONS, 55(18), 2624-2627, 20190304
- A Thiazolothiazole-Based Semiconducting Polymer with Well-Balanced Hole and Electron Mobilities, APPLIED SCIENCES, 9(3), 20190129
- Ni/Co-Catalyzed Homo-Coupling of Alkyl Tosylates, MOLECULES, 24(8), 20190402
- An anthranilamide-substituted borane [H-B(aam)]: its stability and application to iridium-catalyzed stereoselective hydroboration of alkynes, CHEMICAL COMMUNICATIONS, 55(38), 5420-5422, 20190511
- Ester-Functionalized Naphthobispyrazine as an Acceptor Building Unit for Semiconducting Polymers: Synthesis, Properties, and Photovoltaic Performance, MACROMOLECULES, 52(10), 3909-3917, 20190514
- High Operation Stability of Ultraflexible Organic Solar Cells with Ultraviolet-Filtering Substrates, ADVANCED MATERIALS, 31(19), 20190510
- Copper-catalyzed arylstannylation of arynes in a sequence, CHEMICAL COMMUNICATIONS, 55(46), 6503-6506, 20190611
- Copper-Catalyzed B(dan)-Installing Allylic Borylation of Allylic Phosphates, ADVANCED SYNTHESIS & CATALYSIS, 361(10), 2286-2290, 20190514
- ★, Impact of Isomeric Structures on Transistor Performances in Naphthodithiophene Semiconducting Polymers, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 133, 6852-6860, 2011
- ★, Drastic Change of Molecular Orientation in a Thiazolothiazole Copolymer by Molecular-Weight Control and Blending with PC61BM Leads to High Efficiencies in Solar Cells, ADVANCED MATERIALS, 24, 425-430, 2012
- ★, Synthesis, Characterization, and Transistor and Solar Cell Applications of a Naphthobisthiadiazole-Based Semiconducting Polymer, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 134, 3498-3507, 2012
- ★, Naphthodithiophene-Naphthobisthiadiazole Copolymers for Solar Cells: Alkylation Drives the Polymer Backbone Flat and Promotes Efficiency, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 135, 8834-8837, 2013
- ★, Thiophene–Thiazolothiazole Copolymers: Significant Impact of Side Chain Composition on Backbone Orientation and Solar Cell Performances, ADVANCED MATERIALS, 26, 331-338, 2014
- ★, Implication of Fluorine Atom on Electronic Properties, Ordering Structures, and Photovoltaic Performance in Naphthobisthiadiazole- Based Semiconducting Polymers, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 138, 10265-10275, 2016
- Understanding Comparable Charge Transport Between Edge-on and Face-on Polymers in a Thiazolothiazole Polymer System, ACS APPLIED POLYMER MATERIALS, 1(6), 1257-1262, 20190429
- One-pot Sequential Fluorostannylation-Arylstannylation of Arynes, CHEMISTRY LETTERS, 48(9), 1032-1034, 201909
- Synthesis and Deformable Hierarchical Nanostructure of Intrinsically Stretchable ABA Triblock Copolymer Composed of Poly(3-hexylthiophene) and Polyisobutylene Segments, ACS APPLIED POLYMER MATERIALS, 1(3), 315-320, 201903
- Ultrasonic Spray-Coated Mixed Cation Perovskite Films and Solar Cells, ACS SUSTAINABLE CHEMISTRY & ENGINEERING, 7(16), 14217-14224, 20190819
- Nickel/Cobalt-Catalyzed C(sp(3))-C(sp(3)) Cross-Coupling of Alkyl Halides with Alkyl Tosylates, ACS CATALYSIS, 9(10), 9285-9291, 201910
- Direct Suzuki-Miyaura Coupling with Naphthalene-1,8-diaminato (dan)-Substituted Organoborons, ACS CATALYSIS, 10(1), 346-351, 20200103
- Mixed-Ligand Approach to Palladium-Catalyzed Direct Arylation Polymerization: Synthesis of Donor-Acceptor Polymers Containing Unsubstituted Bithiophene Units, MACROMOLECULES, 53(1), 158-164, 20200114
- Reductive amidation of alkyl tosylates with isocyanates by a Ni/Co-dual catalytic system, CHEMICAL COMMUNICATIONS, 56(8), 1247-1250, 20200125
- ★, Impact of Noncovalent Sulfur-Fluorine Interaction Position on Properties, Structures, and Photovoltaic Performance in Naphthobisthiadiazole-Based Semiconducting Polymers, ADVANCED ENERGY MATERIALS, 10(7), 202002
- Direct Evidence of Less Charge Accumulation in Highly Durable Polymer Solar Cells Using Operando Electron Spin Resonance Spectroscopy, ACS APPLIED ENERGY MATERIALS, 3(2), 2028-2036, 202002
- Semiconducting small molecule/polymer blends for organic transistors, POLYMER, 191, 20200316
- Dithiazolylthienothiophene Bisimide-Based pi-Conjugated Polymers: Improved Synthesis and Application to Organic Photovoltaics as P-Type Semiconductor, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 93(4), 561-567, 202002
- Sequential Ultrasonic Spray-Coating Planar Three Layers for 1 cm(2) Active Area Inverted Perovskite Solar Cells, ENERGY TECHNOLOGY, 8(7), 202007
- Effect of Spacer Length in Naphthobispyrazine-Based pi-Conjugated Polymers on Properties, Thin Film Structures, and Photovoltaic Performances, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 93(8), 949-957, 202005
- pi-Conjugated polymers and molecules enabling small photon energy loss simultaneously with high efficiency in organic photovoltaics, JOURNAL OF MATERIALS CHEMISTRY A, 8(39), 20213-20237, 20201021
- Small-bandgap quinoid-based p-conjugated polymers, JOURNAL OF MATERIALS CHEMISTRY C, 8(41), 14262-14288, 20201107
- Significantly Sensitized Ternary Blend Polymer Solar Cells with a Very Small Content of the Narrow-Band Gap Third Component That Utilizes Optical Interference, MACROMOLECULES, 53(23), 10623-10635, 20201208
- Visible light-driven Giese reaction with alkyl tosylates catalysed by nucleophilic cobalt, RSC ADVANCES, 11(6), 3539-3546, 20210127
- Controlled steric selectivity in molecular doping towards closest-packed supramolecular conductors, COMMUNICATIONS MATERIALS, 1(1), 20201104
- Multi-Channel Pumped Ultrasonic Spray-Coating for High-Throughput and Scalable Mixed Halide Perovskite Solar Cells, ADVANCED MATERIALS INTERFACES, 8(5), 202103
- Donor-Acceptor Polymers Containing 4,8-Dithienylbenzo[1,2-b:4,5-b ']dithiophene via Highly Selective Direct Arylation Polymerization, ACS APPLIED POLYMER MATERIALS, 3(2), 830-836, 20210212
- Analyses of PTzNTz Polymer Solar Cells Using ESR Spectroscopy, JOURNAL OF PHOTOPOLYMER SCIENCE AND TECHNOLOGY, 33(1), 97-102, 2020
- Spray deposition of NiOx hole transport layer and perovskite photoabsorber in fabrication of photovoltaic mini-module, JOURNAL OF POWER SOURCES, 491, 20210415
- N-type Semiconducting Polymers Based on Dicyano Naphthobisthiadiazole: High Electron Mobility with Unfavorable Backbone Twist, CHEMISTRY OF MATERIALS, 33(6), 2218-2228, 20210323
- Self-powered ultraflexible photonic skin for continuous bio-signal detection via air-operation-stable polymer light-emitting diodes, NATURE COMMUNICATIONS, 12(1), 20210414
- Bithiazole Dicarboxylate Ester: An Easily Accessible Electron-Deficient Building Unit for pi-Conjugated Polymers Enabling Electron Transport, MACROMOLECULES, 54(7), 3489-3497, 20210413
- One-Step Spray-Coated All-Inorganic CsPbI2Br Perovskite Solar Cells, ACS APPLIED ENERGY MATERIALS, 4(6), 5466-5474, 20210628
- Molecular Understanding of How the Interfacial Structure Impacts the Open-Circuit Voltage of Highly Crystalline Polymer Solar Cells, ACS APPLIED MATERIALS & INTERFACES, 13(29), 34357-34366, 20210728
- Effect of Ester Side Chains on Photovoltaic Performance in Thiophene-Thiazolothiazole Copolymers, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 94(8), 2019-2027, 202108
- Extended pi-Electron Delocalization in Quinoid-Based Conjugated Polymers Boosts Intrachain Charge Carrier Transport, CHEMISTRY OF MATERIALS, 33(21), 8183-8193, 20211109
- Contrasting Effect of Side-Chain Placement on Photovoltaic Performance of Binary and Ternary Blend Organic Solar Cells in Benzodithiophene-Thiazolothiazole Polymers, CHEMSUSCHEM, 14(22), 5032-5041, 20211119
- Pronounced Backbone Coplanarization by p-Extension in a Sterically Hindered Conjugated Polymer System Leads to Higher Photovoltaic Performance in Non-Fullerene Solar Cells, ACS APPLIED MATERIALS & INTERFACES, 13(47), 56420-56429, 20211201
Awards
- 2013, SPSJ Hitachi Award, Society of Polymer Science Japan, 縮環π電子系縮環π電子系を基盤とする高性能半導体ポリマーの開発
External Funds
Acceptance Results of Competitive Funds
- NEDO Feasibility Study Program, 2021/05, 2023/03
- Strategic Basic Research Programs(CREST), 2021/04/01, 2023/03/31
- JST-Mirai Program, 2020/11/01, 2024/03/31
- Strategic Basic Research Programs(ALCA), 2016/10/01, 2019/03/31
- KAKENHI(Grant-in-Aid for Scientific Research (B)), 2016, 2018
- JST-Mirai Program, 2020/11/01, 2023/03/31