20 results match your criteria: "Osaka University 2-1 Yamada-oka[Affiliation]"
Chem Sci
January 2024
Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University 2-1 Yamada-oka Osaka 565-0871 Japan
Electrocatalytic and thermocatalytic CO conversions provide promising routes to realize global carbon neutrality, and the development of corresponding advanced catalysts is important but challenging. Hollow-structured carbon (HSC) materials with striking features, including unique cavity structure, good permeability, large surface area, and readily functionalizable surface, are flexible platforms for designing high-performance catalysts. In this review, the topics range from the accurate design of HSC materials to specific electrocatalytic and thermocatalytic CO conversion applications, aiming to address the drawbacks of conventional catalysts, such as sluggish reaction kinetics, inadequate selectivity, and poor stability.
View Article and Find Full Text PDFRSC Adv
January 2024
Department of Molecular Chemistry, Division of Applied Chemistry, Graduate School of Engineering, Osaka University 2-1 Yamada-oka Suita Osaka 565-0871 Japan.
We developed self-assembled peptides containing a partial amyloid β protein sequence and a metal-coordination site. The amyloid fibril-copper complexes exhibited excellent reactivity and moderate enantioselectivity in Michael addition reactions with 2-azachalcone and dimethylmalonate. The catalytic amyloids were characterized using various measurements to confirm their amyloid-like nanofibre structures.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2024
Department of Macromolecular Science, Graduate School of Science, Osaka University. 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
A strong, tough, and stable adhesion system used in various environments must be developed. A long-lasting adhesion system should effectively perform in the following five aspects: adhesion strength, toughness, energy dissipation property, self-restoration property, and creep resistance property. However, these properties are difficult to balance using conventional adhesives.
View Article and Find Full Text PDFNanoscale Adv
February 2022
Department of Applied Chemistry, Graduate School of Engineering, Osaka University 2-1 Yamada-oka Suita Osaka 565-0871 Japan
Ternary and quaternary semiconductor quantum dots (QDs) are candidates for cadmium-free alternatives. Among these, semiconductors containing elements from groups 11, 13, and 16 (, I-III-VI) are attracting increasing attention since they are direct semiconductors whose bandgap energies in the bulk state are tunable between visible and near infrared. The quaternary system of alloys consisting of silver indium sulfide (AgInS; bandgap energy: = 1.
View Article and Find Full Text PDFRSC Adv
July 2022
Department of Applied Chemistry, Graduate School of Engineering, Osaka University 2-1 Yamada-oka Suita 565-0871 Japan
Photoluminescent carbon dots (CDs) possess several advantages, which include high stability and a non-toxicity that are essential in different applications such as catalysis, drug delivery, and sensors. The presence of heteroatoms modifies their physicochemical characteristics. In this work, a combination of CDs is manufactured utilizing a solvothermal technique using citric acid and thiourea.
View Article and Find Full Text PDFRSC Adv
May 2022
Department of Applied Chemistry, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan
Pt-nanoparticle-supported graphene nanoplatelets (Pt/GNPs) and multiwalled carbon nanotube composite (Pt/MWCNTs) electrocatalysts for the oxygen reduction reaction (ORR) can be prepared using a one-pot method through the pyrolytic decomposition of the platinum precursor, platinum(ii) bis(acetylacetonate) (Pt(acac)) in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([Cmim][TfN]) or ,,-trimethyl--propylammonium bis(trifluoromethanesulfonyl)amide ([N][TfN]) ionic liquids (ILs) with the target sp carbon support. In this one-pot pyrolysis method, which does not require any reagents to reduce Pt metal precursors or stabilize Pt nanoparticles, Pt nanoparticles are readily immobilized onto the sp surface by a thin IL layer formed at the interface, which can work as a binder. We used three types of sp carbon materials with different geometric shapes (graphene nanoplatelets with <3 (GNPs-3) and 18-24 layers (GNPs-20) and multiwalled carbon nanotubes (MWCNTs)) to investigate Pt nanoparticle formation and anchoring.
View Article and Find Full Text PDFChem Sci
July 2021
Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University 2-1 Yamada-oka Suita Osaka 565-0871 Japan
Production of methanol from anthropogenic carbon dioxide (CO) is a promising chemical process that can alleviate both the environmental burden and the dependence on fossil fuels. In catalytic CO hydrogenation to methanol, reduction of CO to intermediate species is generally considered to be a crucial step. It is of great significance to design and develop advanced heterogeneous catalysts and to engineer the surface structures to promote CO-to-methanol conversion.
View Article and Find Full Text PDFScience
July 2021
Surface and Interface Science Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
Ways to characterize and control excited states at the single-molecule and atomic levels are needed to exploit excitation-triggered energy-conversion processes. Here, we present a single-molecule spectroscopic method with micro-electron volt energy and submolecular-spatial resolution using laser driving of nanocavity plasmons to induce molecular luminescence in scanning tunneling microscopy. This tunable and monochromatic nanoprobe allows state-selective characterization of the energy levels and linewidths of individual electronic and vibrational quantum states of a single molecule.
View Article and Find Full Text PDFNanoscale Adv
February 2021
Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface (LRS) Paris F-75005 France
We report the first preparation of small gold-nickel (AuNi) bimetallic nanoparticles (<5 nm) supported on titania by the method of galvanic replacement reaction (GRR), evidenced by the replacement of Ni atoms by Au atoms according to the stoichiometry of the reaction. We showed that this preparation method allowed not only the control of the gold and nickel contents in the samples, but also the formation of small bimetallic nanoparticles with strained core-shell structures, as revealed by aberration-corrected scanning transmission electron microscopy in combination with energy-dispersive X-ray spectroscopy mapping. The catalytic characterization by the probe reaction of semi-hydrogenation of butadiene showed that the resulting nickel-based nanocatalysts containing a small amount of gold exhibited higher selectivity to butenes than pure nickel catalysts and a high level of activity, closer to that of pure nickel catalysts than to that of pure gold catalysts.
View Article and Find Full Text PDFRSC Adv
August 2020
Graduate School of Engineering, Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8603 Japan
Nanoparticles composed of molybdenum oxide, MoO , were successfully prepared by room-temperature ionic liquid (RTIL)/metal sputtering followed by heat treatment. Hydroxyl groups in RTIL molecules retarded the coalescence between MoO NPs during heat treatment at 473 K in air, while the oxidation state of Mo species in MoO nanoparticles (NPs) could be modified by changing the heat treatment time. An LSPR peak was observed at 840 nm in the near-IR region for MoO NPs of 55 nm or larger in size that were annealed in a hydroxyl-functionalized RTIL.
View Article and Find Full Text PDFChempluschem
June 2019
Department of Chemistry Graduate School of Science, Kitasato University 1-15-1 Kitasato Minami-ku, Sagamihara, Kanagawa, 252-0373, Japan.
Rhodium dinuclear complexes (1-3) with azulene moieties as equatorial ligands were obtained by reacting Rh (OAc) with guaiazulene-2-carboxylic acid, azulene-2-carboxylic acid, and azulene-1-carboxylic acid, respectively. The molecular structures in their crystalline states were determined by X-ray diffraction to be 1 ⋅ (H O) , 1 ⋅ (MeCN) , 2 ⋅ (MeCN) , and 3 ⋅ (DMF) , which were coordinated with the crystallization solvent at the axial positions. Among these, the crystal packing of 1 ⋅ (H O) , 1 ⋅ (MeCN) , and 3 ⋅ (DMF) revealed the formation of one-dimensional stacked chains nearly along the axial direction and of two-dimensional stacked sheets along the equatorial direction.
View Article and Find Full Text PDFRSC Adv
October 2019
Biosensors and Biotechnology Laboratory, Chemical Science Programme, Faculty of Science, Universiti Brunei Darussalam Jalan Tungku Link, Gadong BE 1410 Brunei Darussalam
RSC Adv
July 2019
Department of Chemical Science and Engineering, Tokyo Institute of Technology Meguro-ku Tokyo 152-8552 Japan
A synthetic route to embed aggregation-induced-emission-(AIE)-active luminophores in polycarbonates (PCs) in various ratios is reported. The AIE-active monomer is based on the structure of 9,10-bis(piperidyl)anthracene. The obtained PCs display good film-forming properties, similar to those observed in poly(bisphenol A carbonate) (Ba-PC).
View Article and Find Full Text PDFNanoscale Adv
March 2019
Department of Precision Science and Technology, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan
Single-atom catalysis, which utilizes single atoms as active sites, is one of the most promising ways to enhance the catalytic activity and to reduce the amount of precious metals used. Platinum atoms deposited on graphene are reported to show enhanced catalytic activity for some chemical reactions, methanol oxidation in direct methanol fuel cells. However, the precise atomic structure, the key to understand the origin of the improved catalytic activity, is yet to be clarified.
View Article and Find Full Text PDFBisphosphonates are commonly used for the treatment of bone disorders such as osteoporosis; however, the mechanism by which they affect the dynamics of living mature osteoclasts in vivo remains unknown. Here, we describe the short-term effects of different bisphosphonates on controlling the bone resorptive activity of mature osteoclasts in living bone tissues of mice using intravital two-photon microscopy with a pH-sensing chemical fluorescent probe. Three types of nitrogen-containing bisphosphonates, risedronate, alendronate, and minodronate, inhibited osteoclastic acidification during osteoporotic conditions just 12 hours after i.
View Article and Find Full Text PDFJ Biomed Mater Res A
January 2016
Department of Bioengineering, 301 Rhodes Engineering Research Center, Clemson University, Clemson, South Carolina, 29634-0905.
Rev Sci Instrum
February 2012
Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan.
An electron cyclotron resonance ion source (ECRIS) is used to generate multicharged ions for many kinds of the fields. We have developed an evaporator by using induction heating method that can generate pure vapor from solid state materials in ECRIS. We develop the new matching and protecting circuit by which we can precisely control the temperature of the induction heating evaporator.
View Article and Find Full Text PDFAdv Mater
August 2011
Department of Applied Chemistry, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
Biosci Biotechnol Biochem
December 2004
International Center for Biotechnology, Osaka University 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
Human lactoferrin was produced in genetically engineered rice. N-linked glycan structures of recombinant human lactoferrin were determined. The oligosaccharides liberated by hydrazinolysis were labeled with 2-aminopyridine (PA).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2000
Department of Material and Life Science Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan).
By using molecular oxygen bis(µ-oxo)dicopper(III) complexes can be produced from Cu(I) complexes with ligand L(X) (L(X)=p-substituted N-ethyl-N-[2-(2-pyridyl)ethyl]-2-phenylethylamine; X=OMe, Me, H, Cl, NO(2)) in which the benzylic position of the ligand is activated and hydroxylated by the Cu(2)O(2) core (see reaction scheme). Detailed characterization of this new C-H bond activation reaction by the bis(µ-oxo)dicopper(III) core reveals important information on the fundamental chemistry underlying copper monooxygenase reactivity.
View Article and Find Full Text PDF