A5045338955- Electrocatalysts for Energy Conversion
- Catalytic Processes in Materials Science
- CO2 Reduction Techniques and Catalysts
- Advanced battery technologies research
- Hydrogen Storage and Materials
- Fuel Cells and Related Materials
- X-ray Diffraction in Crystallography
- Ammonia Synthesis and Nitrogen Reduction
- Ionic liquids properties and applications
- Advanced Photocatalysis Techniques
- Nanomaterials for catalytic reactions
- nanoparticles nucleation surface interactions
- Advanced NMR Techniques and Applications
- Crystallization and Solubility Studies
- Metal-Organic Frameworks: Synthesis and Applications
- Magnetic properties of thin films
- Supercapacitor Materials and Fabrication
- Covalent Organic Framework Applications
- Advanced Chemical Physics Studies
- Advancements in Solid Oxide Fuel Cells
- Metallic Glasses and Amorphous Alloys
- Copper-based nanomaterials and applications
- Clay minerals and soil interactions
- Magnetism in coordination complexes
- Electrochemical Analysis and Applications
Kyushu University
2016-2025
Tohoku University
2016-2025
Advanced Institute of Materials Science
2024
The University of Tokyo
2024
National Cerebral and Cardiovascular Center
2005-2022
Hokkaido University
2009-2020
Institute for Materials Research, Tohoku University
2020
Hudson Institute
2020
Japan Science and Technology Agency
2011-2016
Centre for Research in Engineering Surface Technology
2014-2015
Electrochemical conversion of CO2 holds promise for utilization as a carbon feedstock and storage intermittent renewable energy. Presently Cu is the only metallic electrocatalyst known to reduce appreciable amounts hydrocarbons, but often wide range products such CO, HCOO–, H2 are formed well. Better catalysts that exhibit high activity especially selectivity specific needed. Here bimetallic Cu–Pd with ordered, disordered, phase-separated atomic arrangements (Cuat:Pdat = 1:1), well two...
The size dependencies of the hydrogen-storage properties in polymer-coated Pd nanoparticles with diameters 2.6 ± 0.4 and 7.0 0.9 nm were investigated by a measurement hydrogen pressure-composition isotherms. Their storage capacities per constituent atom particles decreased decreasing particle size, whereas concentrations two kinds almost same 1.2 times as much, respectively, that bulk palladium after counting zero occupancy on atoms first surface layer particles. Furthermore, apparent...
Abstract Carbon dioxide (CO 2 ) electroreduction reaction RR) offers a promising strategy for the conversion of CO into valuable chemicals and fuels. RR in acidic electrolytes would have various advantages due to suppression carbonate formation. However, its rate is severely limited by slow diffusion absence hydroxide that facilitates an environment. Here, we design optimal architecture gas electrode (GDE) employing copper-based ultrathin superhydrophobic macroporous layer, which highly...
The hydrogen storage properties of metal nanoparticles change with particle size. For example, in a palladium-hydrogen system, the solubility and equilibrium pressure for formation palladium hydride decrease size, whereas platinum, which cannot be stored bulk state, increases. Systematic studies Pd Pt have clarified origins these nanosize effects. We found novel absorption site hetero-interface that forms between core shell Pd/Pt core/shell-type bimetallic nanoparticles. It is proposed...
We have investigated the hydrogen absorption/desorption hysteresis by means of in situ powder X-ray diffraction (XRD) and solid-state 2H NMR to clarify location hydrogen, surface or body, its chemical form, molecular, atomic, as hydride. The present results point out that strongly trapped atoms exist inside Pd nanoparticles due a strong Pd−H bond formation are stabilized lattice nanoparticles, compared bulk Pd.
A new class of monolayer-protected Au clusters with Au-C covalent bonds (organogold clusters) was synthesized by ligating phenylacetylene (PhC≡CH) to PVP-stabilized clusters. Matrix-assisted laser desorption ionization mass spectrometry revealed for the first time a series stable compositions organogold (Au:C(2)Ph)
We have achieved the creation of a solid-solution alloy where Pd and Pt are homogeneously mixed at atomic level, by process hydrogen absorption/desorption as trigger for core (Pd)/shell (Pt) nanoparticles. The structural change from core/shell to solid solution has been confirmed in situ powder X-ray diffraction, energy dispersive spectra, solid-state (2)H NMR measurement, pressure-composition isotherms. successfully obtained Pd-Pt nanoparticles with content 8-21 atom % had higher...
We demonstrate a metal-organic framework (MOF) design for the inclusion of hydroxide ions. Salt method was applied to an alkaline-stable ZIF-8 (ZIF = zeolitic imidazolate framework) introduce alkylammonium hydroxides as ionic carriers. found that tetrabutylammonium salts are immobilized inside pores by hydrophobic interaction between alkyl groups salt and framework, which significantly increases hydrophilicity ZIF-8. Furthermore, including exhibited capacity OH(-) ion exchange, implying...
High-pressure rocksalt ZnO with a band gap of 1.8 eV, which can absorb visible light.
Body-centered-cubic type CuPd nanoalloys were synthesized by a chemical reduction method. Photocatalytic hydrogen evolution and nitrate simultaneously examined over deposited on TiO2 (CuPd/TiO2). The efficiency of CuPd/TiO2 was better than that Pd/TiO2. As for reduction, ammonia selectively (78%) produced with generated photocatalytically CuPd/TiO2. continuous generation nascent atoms the surface nanoalloy, where Cu Pd are homogeneously mixed, led to high selectivity ammonia.
Iridium oxide (IrOx)-based materials are the most suitable oxygen evolution reaction (OER) catalysts for water electrolysis in acidic media. There is a strong demand from industry improved performance and reduction of Ir amount. Here, we report composite catalyst, IrOx–TiO2–Ti (ITOT), with high concentration active OH species mixed valence IrOx on its surface. We have discovered that obtained ITOT catalyst shows an outstanding OER activity (1.43 V vs RHE at 10 mA cm–2) Moreover, no apparent...
Seven amino acids were electrochemically synthesized from biomass-derivable α-keto and NH2OH with faradaic efficiencies (FEs) of 77–99% using an earth-abundant TiO2 catalyst. Furthermore, we newly constructed a flow-type electrochemical reactor, named "polymer electrolyte acid electrosynthesis cell", achieved continuous production alanine FE 77%.
Abstract Current greenhouse gas emissions suggest that keeping global temperature increase below 1.5 degrees, as espoused in the Paris Agreements will be challenging, and to do so, achievement of carbon neutrality is utmost importance. It also clear no single solution can meet neutral challenge, so it essential for scientific research cover a broad range technologies initiatives which enable realization free energy system. This study details broad, yet targeted themes being pioneered within...
The oxygen evolution reaction (OER) is a critical element for all sorts of reactions that use water as hydrogen source, such and electrochemical CO2 reduction, novel design principles provide highly active sites on OER electrocatalysts push the limits their practical applications. Herein, Au-cluster loading unilamellar exfoliated layered double hydroxide (ULDH) demonstrated to fabricate heterointerface between Au clusters ULDHs an site, which accompanied by oxidation state modulation site...
Nicotinamide adenine dinucleotide (NAD+) and its reduced form (NADH) are key cofactors serving as essential hydrogen acceptors donors to facilitate energy material conversions under mild conditions. We demonstrate direct electrochemical conversion achieve highly efficient regeneration of enzymatically active 1,4-NADH using a Pt-modified TiO2 catalyst grown directly on Ti mesh electrode (Pt-TOT). Spectral analyses revealed that defects formed by the inclusion Pt species in lattice play...
We have investigated the hydrogen absorption behavior of Pd/Pt nanoparticles with a core/shell-type structure. From results pressure−composition (PC) isotherm and solid-state 2H NMR measurements, it was revealed that can absorb hydrogen, most absorbed atoms are situated around interfacial region between Pd core Pt shell nanoparticles, indicating core/shell boundary plays an important role in formation hydride phase nanoparticles.
Rh and Ag are the elements neighboring Pd, which is well known as a hydrogen-storage metal. Although do not possess properties, can Ag-Rh alloys actually store hydrogen? solid-solution have been explored in past because they mix with each other at atomic level, even liquid phase. We used chemical reduction method to obtain such alloys, XRD STEM-EDX give clear evidence that mixed level. From measurements of hydrogen pressure-composition isotherms solid-state (2)H NMR, we revealed absorb...
Organogold clusters Au(54)(C(2)Ph)(26) were selectively synthesized by reacting polymer-stabilized Au (1.2 ± 0.2 nm) with excess phenylacetylene in chloroform.
Photocatalytic activity of pure TiO2 is limited to ultraviolet (UV) light due the wide bandgap anatase and rutile phases. The high-pressure phases can theoretically coincide with visible light, but these are unstable at ambient pressure. In this work, TiO2-II (columbite) phase large fractions oxygen vacancies was stabilized by inducing plastic strain under 6 GPa. material could absorb as a consequence narrowing ∼0.7 eV. Formation nanosized enhanced hydrogen generation efficiency improved...
The synergy between Pd atoms, CNT and MnO<sub>2</sub> gives rises to significantly enhanced activity, selectivity stability of Pd/MnO<sub>2</sub>–CNT for oxygen electrocatalysis. assembled rechargeable metal air battery delivered high performance with cycling stability.
An MnO<sub>2</sub>-supported atomic Pd catalyst can actively, selectively and stably convert HMF into FDCA.