A5089644812- Advanced Chemical Physics Studies
- Force Microscopy Techniques and Applications
- Nanocluster Synthesis and Applications
- Machine Learning in Materials Science
- Catalytic Processes in Materials Science
- Molecular Junctions and Nanostructures
- Catalysis and Oxidation Reactions
- X-ray Diffraction in Crystallography
- Fullerene Chemistry and Applications
- Diamond and Carbon-based Materials Research
- Graphene research and applications
- Crystallization and Solubility Studies
- High-pressure geophysics and materials
- Advanced Photocatalysis Techniques
- Quantum Dots Synthesis And Properties
- Surface and Thin Film Phenomena
- Porphyrin and Phthalocyanine Chemistry
- Metal-Organic Frameworks: Synthesis and Applications
- Conducting polymers and applications
- Organic Electronics and Photovoltaics
- Chalcogenide Semiconductor Thin Films
- Advanced Nanomaterials in Catalysis
- Covalent Organic Framework Applications
- Luminescence and Fluorescent Materials
- Perovskite Materials and Applications
Yokohama City University
2019-2025
Hokkaido University
2015-2020
Sapporo Science Center
2019
National Defense Academy of Japan
1982
This article reports implementation and performance of the artificial force induced reaction (AFIR) method in upcoming 2017 version GRRM program (GRRM17). The AFIR method, which is one automated path search methods, induces geometrical deformations a system by pushing or pulling fragments defined an force. In GRRM17, three different algorithms, that is, multicomponent algorithm (MC-AFIR), single-component (SC-AFIR), double-sphere (DS-AFIR), are available, where MC-AFIR was only has been...
Abstract Single‐atom (SA) catalysts exhibit high activity in various reactions because there are no inactive internal atoms. Accordingly, SA cocatalysts also an active research fields regarding photocatalytic hydrogen (H 2 ) evolution which can be generated by abundant water and sunlight. Herein, it is investigated whether 10 transition metal elements work as on graphitic carbon nitride (g‐C 3 N 4 ; i.e., gCN), a promising visible‐light‐driven photocatalyst. A method established to prepare...
Abstract In this account, a technical overview of the artificial force induced reaction (AFIR) method is presented. The AFIR one automated reaction‐path search methods developed by authors, and has been applied extensively to variety chemical reactions, such as organocatalysis, organometallic catalysis, photoreactions. There are two modes in method, i.e., multicomponent mode single‐component mode. former bimolecular reactions latter unimolecular isomerization dissociation reactions. Five...
The inclusion properties of various metal ions in Ni 6 (PET) 12 were investigated and it was found that selectively includes gold ions.
Practical electrochemical water splitting and carbon-dioxide reduction are desirable for a sustainable energy society. In particular, facilitating the oxygen evolution reaction (OER, at anode) will increase efficiency of these reactions. Nickel (Ni) compounds excellent OER catalysts under basic conditions, atomically precise Ni clusters have been actively studied to understand their complex mechanisms. this study, we evaluated geometric/electronic structure tiara-like metal nanoclusters...
Tailormade bottom-up synthesis of covalent organic frameworks (COFs) from various functional building blocks offer not only tunable topology and pore size but also multidimensional properties. High crystallinity is one the prerequisites for their structures associated physicochemical Among different π-conjugated motifs constructing COFs, pyrene-based tetragonal are effective in achieving highly ordered crystalline states. In present research, we demonstrated that substitution pyrene with...
This work present results of a systematic investigation adsorption and dissociation H2 on the neutral, positively, negatively charged gold clusters Aunq (n = 2–11; q 0, ±1) using global reaction route mapping (GRRM) technique combined with anharmonic downward distortion following (ADDF) artificial force-induced (AFIR) methods. An exhaustive search for pathways is performed not only most stable cluster structures but also large number low-energy isomers, allowing structural transformations...
Analysis of a reaction on solid surface is an important task for understanding the catalytic mechanism. In this study, we studied CO oxidation Pt(111) by using artificial force induced (AFIR) method. A systematic path search was done, and route network created. This included not only bond rearrangement paths but also migration adsorbed species. Then, obtained analyzed kinetics method called rate constant matrix contraction (RCMC). It found that bottleneck overall CO2 generation step from...
Interfaces in nanocarbon materials are highly important, as they determine the properties of carbon-based devices. In terms carrier and thermal transport properties, interfacial features often more important than intrinsic characteristics. Herein, we describe how 1 min Joule annealing carbon nanotube (CNT) yarns can convert amorphous into graphene fragments. After annealing, have obtained multiwalled CNT with extremely high Seebeck coefficients (±100 μV/K) thermoelectric power factor (400...
Perovskite solar cells have been attracting considerable attention because of their high power conversion efficiency (PCE). However, is compromised by the defect sites at perovskite surface, where...
Mimicking the interconvertible carbon allotropes of 2-dimensional (2D) graphene and 1-dimensional (1D) nanotubes (CNTs), herein we report in situ transformation 2D π-conjugated covalent organic frameworks (COFs) sheet into 1D nanotubular structures via self-assembly sheets at solvent interfaces. The facile “roll-sheets” resulted coaxial with uniform cross-sectional diameter, which was realized for diazapyrene-based COFs but not corresponding pyrene COF, although both possess similar chemical...
We propose an approach to perform the global search for low-lying crystal structures from first principles, by combining artificial force induced reaction (AFIR) method and periodic boundary conditions (PBCs). The AFIR has been applied extensively molecular systems elucidate mechanism of chemical reactions such as homogeneous catalysis. present PBC/AFIR found 274 local minima carbon crystals in ${\mathrm{C}}_{8}$ unit cell described generalized gradient approximation--Perdew-Burke-Ernzerhof...
Recently, organic donor-acceptor (D-A) cocrystals have attracted special interest as functional materials because of their unique chemical and physical properties that are not exhibited by simple mixtures components. Herein, we report the preparation one-dimensional novel D-A from C60 5,10,15,20-tetrakis(3,5-dimethoxyphenyl)porphyrin (3,5-TPP); these near-infrared (NIR) light-sensing abilities, despite each component molecule individually having no NIR properties. Micrometer-sized...
In this study, artificial force induced reaction (AFIR) method, which has been utilized extensively in molecular systems, was applied to surface adsorbed species. A systematic strategy for obtaining path networks species is described future applications various reactions. As a case global route mapping on the potential energy (PES) of H2O Cu(111) performed. Global performed by method. The resulting network systematically analyzed kinetic method called rate constant matrix contraction.
In nanocatalysis, growing attention has recently been given to investigation of energetically low-lying structural isomers atomic clusters, because some can demonstrate better catalytic activity than the most stable structures. this study, we present a comparative for NO dissociation pair degenerated Cu13 cluster having C2 and C s symmetries. It is shown that although these have similar structural, electronic, optical properties, they possess very different activities. The effect...
Extensive research has been recently conducted to improve the power conversion efficiency (PCE) of perovskite solar cells. However, charge carriers are easily trapped by defect sites located at interface between layer and electrode, which decreases PCE. To reduce such sites, passivation technique is frequently employed coat small molecules on surface during manufacturing process. clarify mechanism from a molecular viewpoint, we performed density functional theory calculations target Pb-free...
The ambipolar triclinic C 60 /Fc nanosheet FETs were converted to n-type face-centered cubic due the loss of ferrocene with void formation upon heating at 150 °C.
In this study, a systematic search for structures of carbon crystals under high pressure was performed by using the artificial force induced reaction method including periodic boundary conditions. To perform an arbitrary pressure, algorithm to take account implemented in GRRM program. At 100 GPa, generated 710 unique automatically. These were compared with 982 obtained zero pressure. The at GPa much denser than those Besides, new that diamond GPa.
Single-Atom Catalysts In article number 2303321, Yuichi Negishi, Tokuhisa Kawawaki, and co-workers create single-atom (SA) photocatalysts with high loading weight. Pd SA-loaded carbon nitride (g-C3N4) exhibit the highest photocatalytic H2-evolution activity regarding various metal species because their electronic structures are suitable for proton adsorption. Finally, in comparison to Pd-nanoparticles cocatalyst, 8.6 times higher rate per active site of SA is achieved.
In this study, we focused on the effect of pressure crystal structures dioxides group 14 elements, i.e. SiO2, GeO2, and CO2. Systematic searches for their using artificial force induced reaction method generated 219 147, 102 63, 148 76 CO2, respectively, at 1 106 atm. At atm, cristobalite-like, quartz, anatase-like, stishovite were stable SiO2 GeO2. CaCl2 type relatively atm molecular crystals most stable, whereas, quartz-like cristobalite-like obtained as We discuss these dependent...
The intersystem crossing (ISC) pathways of triplet benzene molecules in a crystal were investigated theoretically. A combination the gradient projection (GP) method, which is standard method for optimizing seam two potential energy surfaces, and single-component artificial-force-induced reaction (SC-AFIR) (GP/SC-AFIR) was used. This first reported use GP/SC-AFIR calculation using density functional theory with periodic boundary conditions. systematic search minimum-energy structures seams...
Abstract Catalytic bond activation pathways of diatomic molecules on small metal clusters have been studied by density functional theory calculations. The focus this study is dissociation NO, N 2 , and O hexamers eight transition metals (Ni, Cu, Rh, Pd, Ag, Ir, Pt, Au). For all the 24 cases, lowest energy structures at molecular‐adsorption state, state (TS), dissociative‐adsorption were identified a systematic procedure. At TS 20 hexamer moiety took different shape from bare hexamers....
In recent years, supramolecular cocrystals containing organic donors and acceptors have been explored as active components in field-effect transistors (FETs). Herein, we report the synthesis of novel single-cocrystal nanoribbons with ambipolar charge transport characteristics from C70 5,10,15,20-tetrakis(3,5-dimethoxyphenyl)porphyrin (3,5-TPP) a 3 : 2 ratio. The C70/3,5-TPP exhibited new strong absorption band near-infrared region, indicating presence charge-transfer interactions between...