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γ-Butyrolactone Synthesis from Allylic Alcohols Using the CO_(2)Radical Anion

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Precision Chemistry

Precision Chemistry 2024年第3期2卷 88-95页

作者： Saeesh R.Mangaonkar Hiroki Hayashi Wataru Kanna Suvankar Debbarma Yu Harabuchi Satoshi Maeda Tsuyoshi Mita Institute for Chemical Reaction Design and Discovery(WPI-ICReDD) Hokkaido UniversitySapporoHokkaido 001-0021Japan jst ERATO Maeda Artificial Intelligence in Chemical Reaction Design and Discovery ProjectSapporoHokkaido 060-0810Japan Department of Chemistry Faculty of ScienceHokkaido UniversitySapporoHokkaido 060-0810Japan Research and Services Division of Materials Data and Integrated System(MaDIS) National Institute for Materials Science(NIMS)TsukubaIbaraki 305-0044Japan

γ-Butyrolactone structures are commonly found in various natural products and serve as crucial building blocks in organic synthesis.Consequently,the development of methods for synthesizingγ-butyrolactones has garnered significant interest within the organic synthesis community.In this study,we present a direct and highly efficient approach for the synthesis ofγ-butyrolactones from allylic alcohols.Notably,this study represents the first instance ofγ-butyrolactone synthesis initiated by radical hydrocarboxylation using CO_(2)^(•–),generated from metal formates,followed by cyclization.This two-step process is achieved through the synergistic interaction of photoredox and hydrogen atom transfer(HAT)catalysis,resulting in the production ofγ-butyrolactones with exceptional efficiency.Additionally,when employingα,α-diaryl allylic alcohol derivatives as substrates,the reaction involves 1,2-aryl migration,which occurs concomitantly with CO_(2)^(•–)addition,leading to the formation of 4,5-substituted lactones in a good yield.The artificial force induced reaction(AFIR)method identified the preferred 1,2-aryl migration pathway along with potential byproduct pathways,in which the targeted 1,2-migration was found to be the most plausible pathway.

关键词： CO_(2) lactone radical photoredox visible light carboxylation calculation DFT

Bandgap-tunable lateral and vertical heterostructures based on monolayer Mo1-xWxS2 alloys

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Nano Research 2015年第10期8卷 3261-3271页

作者： Yu Kobayashi Shohei Mori Yutaka Maniwa Yasumitsu Miyata DepartmentofPhysics TokyoMetropolitanUniversityHachiojiTokyo192-0397Japan jst PRESTOKawaguchiSaitama332-0012Japan

有特定的 bandgaps 的二维的半导体的 heterostructures 的制造是认识到这些材料的完整的潜力在的一条重要途径电子并且 optoelectronic 设备。几个组最近基于象 WSe 2, MoSe 2, WS 2, 和瞬间 2 那样的典型半导体的转变金属 dichalcogen... 详细信息

有特定的 bandgaps 的二维的半导体的 heterostructures 的制造是认识到这些材料的完整的潜力在的一条重要途径电子并且 optoelectronic 设备。几个组最近基于象 WSe 2, MoSe 2, WS 2, 和瞬间 2 那样的典型半导体的转变金属 dichalcogenides (TMDC ) 的单层报导了侧面、垂直的 heterostructures 的直接生长。这里，我们基于 bandgap 悦耳的瞬间 1-x W x 由 WO 3 和哞 3 的有图案的薄电影的 sulfurization 的 S 2 合金单层。这些有图案的电影能够在水晶生长阶段期间由转变金属的散开产生许多集中坡度。在高温度下面，这导致瞬间 1-x W x 有各种各样的作文和 bandgaps 的 S 2 合金，在底层上取决于晶体的位置。这些合金的 Heterostructures 在低温度的生长期间在一个单个领域以内在 W/Mo 的比率通过逐步的变化被获得。单层瞬间 1-x W x S 2 合金，经常甚至在轻轻的条件下面降级，被涂层完成有另外的单层的合金。现在的调查结果表明学习并且优化基于 TMDC 的 heterostructures 的光、电的性质在未来设备应用允许材料的使用的一个有效工具。

关键词：半导体异质结构合金膜带隙单层可调光电子器件硫化物膜直接生长

Nanofluidics for sub-single cellular studies:Nascent progress,critical technologies,and future perspectives

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Chinese Chemical Letters 2022年第6期33卷 2799-2806页

作者： Jinbin Yang Yan Xu Department of Chemical Engineering Graduate School of EngineeringOsaka Prefecture UniversitySakaiOsaka 599-8570Japan Japan Science and Technology Agency(jst) PRESTOKawaguchiSaitama332-0012Japan NanoSquare Research Institute Research Center for the 21^(st)CenturyOrganization for Research PromotionOsaka Prefecture UniversitySakaiOsaka 599-8570Japan

In the field of cell studies,there is a burgeoning trend to further downscale the investigation from a single-cell level to a sub-single-cell level.Subcellular matter is the basic content in cells and correlates with cell heterogeneity.Sub-single cellular studies focus on the subcellular matter in single cells and aim to understand the details and heterogeneity of individual cells in terms of the subcellular matter or even at the single component/vesicle/molecule level.Hence,sub-single cellular studies can provide deeper insights into fundamental cell biology and the development of new diagnostic and therapeutic technologies and applications.Nonetheless,the contents of a single cell are not only ultra-small in volume but also extremely complex in composition,far exceeding the capabilities of most tools used in current cell studies.We believe that nanofluidics holds great potential in providing ideal tools for sub-single cellular studies,not only because of their capability to handle femtoliter/attoliter-scale samples,but also because of their possibility to manipulate and analyze subcellular matters at the single component/vesicle/molecule level in a high-throughput manner.In this review,we summarize the efforts in the field of nanofluidics for sub-single cellular studies,focusing on nascent progress and critical technologies that have the potential to overcome the technical bottlenecks.Some challenges and future opportunities to integrate with information sciences are also discussed.

关键词： Sub-single cellular matter Single cell Single molecule Extracellular vesicles Nanochannel Femtoliter Attoliter Digital Information sciences

Improvement in growth yield of single-walled carbon nanotubes with narrow chirality distribution by pulse plasma CVD

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Frontiers of Chemical Science and Engineering 2019年第3期13卷 485-492页

作者： Bin Xu Toshiro Kaneko Toshiaki Kato Department o f Electronic Engineering Tohoku UniversitySendai 980-8579Japan Japan Science and Technology Agency (jst)-presto Sendai 980-8579Japan

A pulse plasma chemical vapor deposition (CVD) technique was developed for improving the growth yield of single-walled carbon nanotubes (SWNTs) with a narrow chirality distribution. The growth yield of the SWNTs could be improved by repetitive short duration pulse plasma CVD, while maintaining the initial narrow chirality distribution. Detailed growth dynamics is discussed based on a systematic investigation by changing the pulse parameters. The growth of SWNTs with a narrow chirality distribution could be controlled by the difference in the nucleation time required using catalysts comprising relatively small or large particles as the key factor. The nucleation can be controlled by adjusting the pulse on/ofF time ratio and the total processing time.

关键词： single-walled carbon nanotubes chiralitycontrolled synthesis pulse plasma chemical vapor deposition

High-temperature formation phases and crystal structure of hot-pressed thermoelectric compounds with chalcopyrite-type structure

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Rare Metals 2018年第4期37卷 360-368页

作者： Atsuko Kosuga Yosuke Fujii Akito Horie Department of Physical Science Graduate School of ScienceOsaka Prefecture University jst PRESTO Department of Electronics Mathematics and PhysicsGraduate School of EngineeringOsaka Prefecture University

In this study, we introduced the temperaturedependent formation phases and crystallographic parameters of hot-pressed silver gallium telluride AgGaTe2 and copper gallium telluride CuGaTe2 with chalcopyrite structure from 300 to 800 K. These two compounds are potential thermoelectric materials in the intermediate temperature range; however, the temperature-dependent formation phases and crystallographic parameters of hotpressed samples have not yet been analyzed in detail. The crystal structure analysis based on synchrotron X-ray diffraction （SXRD） measurements clarifies that impurity phases such as Te and Ag2Te in the AgGaTe2 matrix and Te and CuTe in the CuGaTe2 matrix appear at some temperature regions above 300 K. The existence of such impurity phases could be correlated with the increases of the electrical resistivity and Seebeck coefficient of the samples after multiple measurement cycles of the temperature-dependent transport properties from 300 to 800 K. The tetragonal lattice parameters a and c, tetragonal lattice volume, thermal expansion coefficients, tetragonal distortion, anion displacement parameter, and isotropic displacement parameter of the hot-pressed AgGaTe2 and CuGaTe2 were also analyzed. These crystallographic parameters are expected to substantially affect the thermoelectric properties of AgGaTe2 and CuGaTe2. Our results provide prospect of the long-term high-temperature stability and clues of the detailed analysis on the transport properties of hot-pressed AgGaTe2 and CuGaTe2, which should aid their development for thermoelectric applications.

关键词： Chalcopyrite Silver gallium telluride Coppergallium telluride Thermoelectric Crystal structure

Zinc-Based Metal-Organic Frameworks for High-Performance Supercapacitor Electrodes:Mechanism Underlying Pore Generation

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Energy & Environmental Materials 2023年第2期6卷 100-112页

作者： Shigeyuki Umezawa Takashi Douura Koji Yoshikawa Daisuke Tanaka Vlad Stolojan S.Ravi P.Silva Mika Yoneda Kazuma Gotoh Yasuhiko Hayashi Seiwa Electric Mfg.Co.Ltd. Kyoto 610-0192Japan Graduate School of Natural Science and Technology Okayama UniversityOkayama 700-8350Japan School of Science and Technology Kwansei Gakuin UniversityHyogo 669-1337Japan JST PRESTO2-1 GakuenHyogo 669-1337Japan Advanced Technology Institute University of SurreyGuilfordSurreyGU27XHUK

Heat treatment of metal-organic frameworks(MOFs)has provided a wide variety of functional carbons coordinated with metal compounds.In this study,two kinds of zinc-based MOF(ZMOF),C_(16)H_(10)O_(4)Zn(ZMOF1)and C_(8)H_(4)O_(4)Zn(ZMOF2),were prepared.ZMOF1 and ZMOF2 were carbonized at 1000℃,forming CZMOF1 and CZMOF2,respectively.The specific surface area(S_(BET))of CZMOF2 was~2700 m^(2)g^(−1),much higher than that of CZMOF1(~1300 m^(2)g^(−1)).A supercapacitor electrode based on CZMOF2 achieved specific capacitances of 360,278,and 221 F g^(−1)at 50,250,and 1000 mA g^(−1)in an aqueous electrolyte(H2SO_(4)),respectively,the highest values reported to date for ZMOF-derived electrodes under identical conditions.The practical applicability of the CZMOF-based supercapacitor was verified in non-aqueous electrolytes.The initial capacitance retention was 78%after 100000 charge/discharge cycles at 10 A g^(−1).Crucially,the high capacitance of CZMOF2 arises from pore generation during carbonization.Below 1000℃,pore generation is dominated by the Zn/C ratio of ZMOFs,as carbon atoms reduce the zinc oxides formed during carbonization.Above 1000℃,a high O/C ratio becomes essential for pore generation because the oxygen functional groups are pyrolyzed.These findings will provide insightful information for other metal-based MOFderived multifunctional carbons.

关键词： metal-organic frameworks pore generation porous carbons supercapacitor zinc oxides

Fabrication of luminescent patterns using aggregation-induced emission molecules by an electrolytic micelle disruption approach

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聚集体(英文)

聚集体(英文) 2023年第1期4卷 231-237页

作者： Yaqian Zhou Elena Villani Tomoyuki Kurioka Yanyun Zhang Ikuyoshi Tomita Shinsuke Inagi Department of Chemical Science and Engineering School of Materials and Chemical TechnologyTokyo Institute of TechnologyYokohamaJapan presto Japan Science and Technology Agency(JST)KawaguchiJapan

Herein,we report an electrochemical strategy that could control the location of aggregation-induced emission(AIE)molecules on patterned electrodes in a precise and facile way,producing photoluminescent and electrochemiluminescent patterns with a variety of colors.A micelle composed of electroactive surfactants was broken during the electrooxidation process,in which AIE molecules inside these micelles were released on patterned electrodes.These patterned electrodes were pretreated by not only metal,but also multifarious conducting polymers(CPs).An in-depth investigation clarified a correlation between the variety of CPs used as electrodes and the oxidation rate of the electroactive surfactant due to different catalytic performances of CPs.Furthermore,combined with wireless and gradient features of bipolar electrochemistry,a gradient luminescent pattern was easily achieved.The current studies suggest more abundant luminescent patterns using AIE luminophores can be developed by such an electrochemical method,in both of graphical shapes and emitting colors.

关键词： aggregation-induced emission bipolar electrochemistry catalysis conducting polymers electrochemiluminescence electrolytic micelle disruption

Charge generation in organic solar cells: Journey toward 20% power conversion efficiency

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Aggregate

Aggregate 2022年第6期3卷 5-33页

作者： Yasunari Tamai Department of Polymer Chemistry Graduate School of EngineeringKyoto UniversityKatsuraNishikyoKyotoJapan Japan Science and Technology Agency(jst) PRESTO4-1-8 Honcho KawaguchiSaitamaJapan

The power conversion efficiencies of organic solar cells(OSCs)have routinely lagged far behind those of their inorganic counterparts.However,owing to the enor-mous contributions of many researchers,the power conversion efficiencies of OSCs have rapidly improved and now exceed 19%.The charge generation mechanisms in OSCs have been heavily debated during this period while acquiring valuable knowl-edge.This review highlights fundamental and cutting-edge research that rationalizes why OSCs can generate photocurrent so efficiently.In particular,a photophysi-cist’s views on exciton diffusion to donor:acceptor interfaces,charge transfer at the donor:acceptor interface,and long-range spatial dissociation of charge transfer states are discussed.Although a general consensus in this area has not been reached yet,recent time-resolved spectroscopic measurements provide important photophys-ical insights that can help achieving a better understanding of the charge generation mechanism in OSCs.Based on these observations,future research directions for realizing further improvements in OSC performance are discussed.

关键词： charge dissociation charge recombination charge separation charge transfer exciton diffusion organic

High-pressure MOCVD growth of InGaN thick films toward the photovoltaic applications

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Fundamental Research 2023年第3期3卷 403-408页

作者： Liwen Sang Meiyong Liao Masatomo Sumiya Xuelin Yang Bo Shen International Center for Materials Nanoarchitectonics(MANA) National Institute for Materials Science(NIMS)1-1 NamikiTsukubaIbaraki 305-0044Japan jst-presto The Japan Science and Technology AgencyTokyo 102-0076Japan Research Center for Functional Materials National Institute for Materials Science1-1 NamikiTsukubaIbaraki 305-0044Japan State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijingChina

The highly efficient photovoltaic cells require the In-rich InGaN film with a thickness more than 300 nm to achieve the effective photo-electricity energy conversion.However,the InGaN thick films suffer from poor crystalline quality and phase separations by using the conventional low-pressure metal organic chemical vapor deposition(MOCVD).We report on the growth of 0.3-1μm-thick InGaN films with a specially designed vertical-type high-pressure MOCVD at the pressure up to 2.5 atms.The In incorporation is found to be greatly enhanced at the elevated pressures although the growth temperatures are the same.The phase separations are inhibited when the growth pressure is higher than atmospheric pressure,leading to the improved crystalline quality and better surface morphologies especially for the In-rich InGaN.The In 0.4 Ga 0.6 N with the thickness of 300 nm is further demonstrated as the active region of solar cells,and the widest photoresponse range from ultraviolet to more than 750 nm is achieved.

关键词： InGaN Solar cell High-pressure MOCVD Photo-electricity energy conversion In-rich XRD