Details of a Researcher - HAMANAKA Yasushi

Papers - HAMANAKA Yasushi

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Luminescence Mechanisms of Quaternary Zn-Ag-In-S Nanocrystals: ZnS:Ag, In or AgInS₂:Zn? Reviewed International journal

ChemPhysChem 26 ( 5 ) e202400316-1 - e202400316-7 2024.11

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley

DOI： 10.1002/cphc.202400316

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Photoexcited Carrier Transfer in CuInS₂ Nanocrystal Assembly by Suppressing Resonant-Energy Transfer Reviewed

Yasushi Hamanaka, Satoshi Okuyama, Rin Yokoi, Toshihiro Kuzuya, Keiki Takeda, Chihiro Sekine

ChemPhysChem 24 ( 21 ) e202300029-1 - e202300029-8 2023.08

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

DOI： https://doi.org/10.1002/cphc.202300029

Fabrication of two-dimensional hybrid organic-inorganic lead halide perovskites with controlled multilayer structures by liquid phase laser ablation Reviewed

Yoshimasa Fukuta, Takumi Miyata, Yasushi Hamanaka

Journal of Materials Chemistry C 11 ( 3 ) 910 - 916 2023.01

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

DOI： 10.1039/d2tc04395e

Size-dependent radiative recombination characteristics of isolated CuInS₂ nanocrystals Reviewed

Journal of Luminescence 252 119353-1 - 119353-7 2022.09

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

DOI： 10.1016/j.jlumin.2022.119353

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Luminescence Enhancement in CuInS₂ Nanoparticles through the Selective Passivation of Nonradiative Recombination Sites by Phosphine Ligands Reviewed

Koichiro Suzuki, Toshihiro Kuzuya, and Yasushi Hamanaka

Journal of Physical Chemistry C 126 ( 39 ) 16751 - 16758 2022.09

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

DOI： 10.1021/acs.jpcc.2c05187

Synthesis and Analysis of Highly Monodispersed Silver Copper Sulfide Nanoparticles Reviewed

Kenshiro Sato, Toshihiro Kuzuya, Yasushi Hamanaka, Shinji Hirai

MATERIALS TRANSACTIONS 62 ( 6 ) 731 - 737 2021.05

Language：English Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Metals and Materials (JIM)

DOI： 10.2320/matertrans.MT-M2020395

Non-vacuum fabrication of bandgap-controlled CZTGS alloy films using CZTS+CZGS mixed nanoparticle inks Reviewed International journal

Y. Hamanaka, K. Matsumoto

Materials Science Forum 1016 509 - 515 2021.01

Authorship：Lead author Language：English Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications Ltd

Ligand-induced luminescence transformation in AgInS₂ nanoparticles:From defect emission to band-edge emission Reviewed International journal

Akemitsu Hirase, Yasushi Hamanaka, Toshihiro Kuzuya

Journal of Physical Chemistry Letters 11 3969 - 3974 2020.04

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：ACS publications

DOI： 10.1021/acs.jpclett.0c01197

Luminescence enhancement mechanisms of AgInS₂/ZnS core/shell nanoparticles fabricated by suppressing quaternary alloying Reviewed International journal

Yasushi Hamanaka, Kento Watanabe, Toshihiro Kuzuya

Journal of Luminescence 217 116794 2019.09

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier

DOI： https://doi.org/10.1016/j.jlumin.2019.116794

Luminescence enhancement mechanisms of AgInS<sub>2</sub>/ZnS core/shell nanoparticles fabricated by suppressing quaternary alloying Reviewed

Yasushi Hamanaka, Kento Watanabe, Toshihiro Kuzuya

Journal of Luminescence 217 116794 2019.09

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier

DOI： 10.1016/j.jlumin.2019.116794

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Syntheis of Ag／AgCuS／CuInS₂ hybrid nanoparticles by reductive cation exchange and their asymmetric heterostructure Reviewed International journal

T. Kuzuya, T. Kuwada, H. Inukai, Y. Hamanaka, S. Hirai

Applied Surface Science 493 1278 - 1285 2019.07

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier

DOI： 10.1016/j.apsusc.2019.07.129

Anisotropic licalized surface plasmon resonances in CuS nanoplates prepared by size-selective precipitation Reviewed International journal

Yasushi Hamanaka, Kaoru Yamada, Tatusnori Hirose, Toshihiro Kuzuya

Japanese Journal of Applied Physics 57 055201 2018.04

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

DOI： 10.7567/JJAP.57.055201

Plasmonic Optical Nonlinearities of Copper Sulfide Nanoparticles Reviewed International journal

Hamanaka, Y., Hirose, T., Yamada, K., Miyagawa, K., & Kuzuya, T.

MRS Advances 3 ( 14 ) 741 - 746 2018.01

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

DOI： 10.1557/adv.2018.91

Fabrication of oxidation-resistant Ge colloidal nanoparticles by pulsed laser ablation in aqueous HCl Reviewed International journal

Yasushi Hamanaka, Masahiro Iwata, Junichi Katsuno

Applied Physics A 123 425 2017.05

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Springer

DOI： 10.1007/s00339-017-1044-9

Synthesis of Ag/CuInS2 Core-Shell Nanoparticles Reviewed

Toshihiro Kuzuya, Takahiko Kuwada, Yasushi Hamanaka, Shinji Hirai

MATERIALS TRANSACTIONS 58 ( 1 ) 65 - 70 2017

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN INST METALS

In this work, the facile synthesis of Ag/CuInS2 composite nanoparticles (NPs) with a core-shell structure is demonstrated for the first time. In our procedure, the pre-formed Ag NPs were subsequently coated with a CuInS2 shell through the thermal decomposition of the metal thiolate complex. The Ag/CuInS2 composite NPs took Ag core-CuInS2 shell structures (Ag(CuInS2) when an oleic acid-oloylamine mixture was used as the co-surfactant. High-resolution transmission electron microscopy (TEM) indicated the epitaxial growth of the CuInS2 shell on the Ag NPs. In the extinction spectrum of the Ag@CuInS2 NPs, the localized surface plasmon resonance (LSPR) peak of the Ag core broadened and red-shifted to 2.21 eV, confirming that the CuInS2 can he tuned by the CuInS2 shell. Finite-difference time-domain (FDTD) simulations indicated the enhancement of the electric field in the CuInS2 shell region and the surface of the A(2)@CulnS(2) NPs. This enhancement effect may improve the efficiency of incident light absorption in CuInS2 quantum dot sensitized solar cells.

DOI： 10.2320/matertrans.M2016026

Web of Science

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Synthesis of highly non-stoichiometric Cu₂ZnSnS₄ nanoparticles with tunable bandgaps Reviewed International journal

Yasushi Hamanaka, Wataru Oyaizu, Masanari Kawase, Toshihiro Kuzuya

Journal of Nanoparticle Research 19 ( 1 ) 9 2016.12

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Springer

DOI： 10.1007/s1105-016-3704-7

Synthesis of highly non-stoichiometric Cu2ZnSnS4 nanoparticles with tunable bandgaps Reviewed

Yasushi Hamanaka, Wataru Oyaizu, Masanari Kawase, Toshihiro Kuzuya

JOURNAL OF NANOPARTICLE RESEARCH 19 ( 1 ) 9 2016.12

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER

Non-stoichiometric Cu2ZnSnS4 nanoparticles with average diameters of 4-15 nm and quasipolyhedral shape were successfully synthesized by a colloidal method. We found that a non-stoichiometric composition of Zn to Cu in Cu2ZnSnS4 nanoparticles yielded a correlation where Zn content increased with a decrease in Cu content, suggesting formation of lattice defects relating to Cu and Zn, such as a Cu vacancy (V-Cu), antisite with Zn replacing Cu (Zn-Cu), and/or defect cluster of V-Cu and Zn-Cu. The bandgap energy of Cu2ZnSnS4 nanoparticles systematically varies between 1.56 and 1.83 eV depending on the composition ratios of Cu and Zn, resulting in a wider bandgap for Cu-deficient Cu2ZnSnS4 nanoparticles. These characteristics can be ascribed to the modification in electronic band structures due to formation of V-Cu and Zn-Cu on the analogy of ternary copper chalcogenide, chalcopyrite CuInSe2, in which the top of the valence band shifts downward with decreasing Cu contents, because much like the structure of CuInSe2, the top of the valence band is composed of a Cu 3d orbital in Cu2ZnSnS4.

DOI： 10.1007/s11051-016-3704-7

Web of Science

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Synthesis of Ag/CuInS₂ Core-Shell Nanoparticles Reviewed

Toshihiro Kuzuya, Takahiko Kuwada, Yasushi Hamanaka, Shinji Hirai

Materials Transactions 58 ( 1 ) 65 - 70 2016.11

Language：English Publishing type：Research paper (scientific journal)

Synthesis of Ag/CuInS<sub>2</sub> Core-Shell Nanoparticles Reviewed

Toshihiro Kuzuya, Takahiko Kuwada, Yasushi Hamanaka, Shinji Hirai

Materials Transactions 58 ( 1 ) 65 - 70 2016.11

Language：English Publishing type：Research paper (scientific journal)

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