A5085378901- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Advanced Battery Technologies Research
- Electron and X-Ray Spectroscopy Techniques
- Extraction and Separation Processes
- Fuel Cells and Related Materials
- Electrocatalysts for Energy Conversion
- Advancements in Solid Oxide Fuel Cells
- Supercapacitor Materials and Fabrication
- Magnetic and transport properties of perovskites and related materials
- Inorganic Chemistry and Materials
- Inorganic Fluorides and Related Compounds
- Advanced battery technologies research
- X-ray Spectroscopy and Fluorescence Analysis
- Electronic and Structural Properties of Oxides
- Catalytic Processes in Materials Science
- Machine Learning in Materials Science
- Semiconductor materials and devices
- X-ray Diffraction in Crystallography
- Layered Double Hydroxides Synthesis and Applications
- Semiconductor materials and interfaces
- Advanced Condensed Matter Physics
- Electrochemical Analysis and Applications
- Chemical Synthesis and Characterization
- Gas Sensing Nanomaterials and Sensors
Ritsumeikan University
2016-2025
Kyoto University
2011-2020
Massachusetts Institute of Technology
2010
Abstract Rechargeable magnesium batteries are poised to be viable candidates for large-scale energy storage devices in smart grid communities and electric vehicles. However, the density of previously proposed rechargeable is low, limited mainly by cathode materials. Here, we present new design approaches order realize a high-energy-density battery system. Ion-exchanged MgFeSiO 4 demonstrates high reversible capacity exceeding 300 mAh·g −1 at voltage approximately 2.4 V vs. Mg. Further,...
Abstract Rechargeable potassium-ion batteries have been gaining traction as not only promising low-cost alternatives to lithium-ion technology, but also high-voltage energy storage systems. However, their development and sustainability are plagued by the lack of suitable electrode materials capable allowing reversible insertion large potassium ions. Here, exploration database for potassium-based has led us discover ion conducting layered honeycomb frameworks. They show capability ions at...
For the development of a rechargeable metal-air battery, which is expected to become one most widely used batteries in future, slow kinetics discharging and charging reactions at air electrode, i.e., oxygen reduction reaction (ORR) evolution (OER), respectively, are critical problems. Here we report that Ruddlesden-Popper-type layered perovskite, RP-LaSr3Fe3O10 (n = 3), functions as reversible electrode catalyst for both ORR OER an equilibrium potential 1.23 V with almost no overpotentials....
All-solid-state batteries with sulfide solid electrolytes (SEs) are promising next-generation energy storage devices that safe and have a cycle life densities. To improve their electrochemical performances, we investigated the reactions of SEs structural changes. The detailed changes in structure electronic states not yet been measured experimentally because difficulty observing microscopic area formed at interface between electrode materials SEs. Thus, prepared composite electrodes composed...
Abstract Designing efficient catalyst for the oxygen evolution reaction (OER) is of importance energy conversion devices. The anionic redox allows formation O-O bonds and offers higher OER activity than conventional metal sites. Here, we successfully prepare LiNiO 2 with a dominant 3 d 8 L configuration ( hole at O p ) under high pressure, achieve double ligand holes since one electron removal occurs orbitals Ni III oxides. exhibits super-efficient among LiMO , R MO (M = transition metal,...
The phase transition between LiFePO4 and FePO4 during nonequilibrium battery operation was tracked in real time using time-resolved X-ray diffraction. In conjunction with increasing current density, a metastable crystal appears addition to the thermodynamically stable phases. gradually diminishes under open-circuit conditions following electrochemical cycling. We propose path that passes through posit new phase's role decreasing nucleation energy, accounting for excellent rate capability of...
Surface analysis: In situ total-reflection fluorescence X-ray absorption spectroscopy showed that reduction of cobalt at the surface a LiCoO2 electrode occurs by contact with liquid electrolyte. An irreversible behavior was observed during first charge/discharge process whereas bulk material reversible behavior. This Co is an initial deterioration.
Abstract Composite electrodes containing active materials, carbon and binder are widely used in lithium-ion batteries. Since the electrode reaction occurs preferentially regions with lower resistance, distribution can be happened within composite electrodes. We investigate relationship between depth direction electronic/ionic conductivity changing porosities. Two dimensional X-ray absorption spectroscopy shows that is porosity Our developed 6-probe method measure The ionic decreased for...
The active ingredient: La0.8Sr0.2CoO3−δ (LSC) epitaxial thin films are prepared on (001)-oriented yttria-stabilized zirconia (YSZ) single crystals with a gadolinium-doped ceria (GDC) buffer layer (see picture). LSC exhibit better oxygen reduction kinetics than bulk LSC. enhanced activity is attributed in part to higher nonstoichiometry. Detailed facts of importance specialist readers published as "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They...
Transient states of phase transition in LiFePO4/FePO4 for lithium ion battery positive electrodes are investigated by time-resolved measurements. To directly detect changes electronic and crystal structures under operation, situ X-ray absorption diffraction measurements performed, respectively. The fraction change estimated the iron valence is similar to electrochemically expected change. transient lattice constant during two reaction clearly observed measurement. nonequilibrium extraction...
Abstract The atomic and electronic structures of binary Li 2 S-P S 5 glasses used as solid electrolytes are modeled by a combination density functional theory (DFT) reverse Monte Carlo (RMC) simulation using synchrotron X-ray diffraction, neutron diffraction Raman spectroscopy data. ratio PS x polyhedral anions based on the spectroscopic results is reflected in glassy 67Li S-33P , 70Li S-30P 75Li S-25P plausible represent lithium ion distributions around them. It found that edge sharing...
Highly dispersed crystalline/amorphous LiFePO<sub>4</sub> (LFP) nanoparticles encapsulated within hollow-structured graphitic carbon were synthesized using an <italic>in situ</italic> ultracentrifugation process.
Lattice strain of Pt-based catalysts reflecting d-band status is the decisive factor their catalytic activity toward oxygen reduction reaction (ORR). For newly arisen monolayer Pt system, however, no general strategy to isolate lattice has been achieved due short-range ordering structure shells on different facets core nanoparticles. Herein, based extended X-ray absorption fine atoms various single crystal facets, we propose an effective methodology for evaluating The quantitative...
The effects of applied pressure on the morphological structure composite electrode and electrochemical properties an all-solid-state battery (ASSB) cell are analysed by X-ray computed tomography.
Depth-resolved X-ray absorption spectroscopy (DR-XAS) measurements were performed for the direct observation of chemical state and local structure at LiCoO2 electrode–solid electrolyte model interface, which can contribute towards enhancement power density in all solid-state lithium batteries. The charge transfer resistance, measured by AC impedance spectroscopy, interface decreased with introduction a NbO2 interlayer while resistance increased ZrO2 MoO2 interlayers. Using DR-XAS depth...
Novel MgFePO<sub>4</sub>F exhibits a promising feasibility as cathode material for Mg batteries in spite of its cationic-disordered crystal structure.
In sheet-type all-solid-state lithium-ion batteries with the sulfide-based solid electrolyte, composite electrodes consist of active material, conductive additive and binder. Thus, they form a three-dimensional ionic electronic conduction pass. electrodes, reaction inhomogeneity derived from their morphology exerts remarkable effect on battery performance. this study, we prepared for electrolyte using different binder materials solvents investigated distribution within 2D-imaging X-ray...
Surface modification effects on interfacial reaction for zirconia (ZrO2) coated lithium cobalt oxide (LiCoO2) are studied. ZrO2-coated LiCoO2 thin-film electrodes prepared by a pulsed laser deposition with different preparation periods. Cyclic voltammetry measurements clearly show that cycle performance and high-potential durability improved the ZrO2 coating. AC impedance spectroscopy reveals there two types of resistance associated coating; one is charge transfer which depends...
Surface coating on lithium‐ion battery cathodes improves their durability at high potentials, which is a well‐known practical application. However, the mechanism still unclear because influences electrode/electrolyte interface few nanometer‐scale and direct observation of under real operating conditions challenging. This study reveals surface effect by using in operando X‐ray absorption spectroscopy (XAS) well‐defined MgO‐coated LiCoO 2 thin‐film electrodes prepared via pulsed laser...
For the further development of lithium-ion batteries, improvement their cyclic performance is crucial. However, mechanism underlying deterioration battery not fully understood. We investigated effects electronic structure at electrode/electrolyte interface on cathode materials via in situ total-reflection fluorescence X-ray absorption spectroscopy. In a LiCoO2 thin-film electrode that exhibits gradual upon subsequent Li ion extractions and insertions (cycling), reduction Co ions was observed...