A5001239255- Ferroelectric and Piezoelectric Materials
- Advancements in Solid Oxide Fuel Cells
- Advanced Battery Materials and Technologies
- Advancements in Battery Materials
- Electronic and Structural Properties of Oxides
- Microwave Dielectric Ceramics Synthesis
- Multiferroics and related materials
- Magnetic and transport properties of perovskites and related materials
- Gas Sensing Nanomaterials and Sensors
- Education and Learning Interventions
- Electrocatalysts for Energy Conversion
- ZnO doping and properties
- Advanced Battery Technologies Research
- Acoustic Wave Resonator Technologies
- Psychosocial Factors Impacting Youth
- Catalytic Processes in Materials Science
- Educational Systems and Policies
- Copper-based nanomaterials and applications
- Supercapacitor Materials and Fabrication
- Nuclear Materials and Properties
- Thermal Expansion and Ionic Conductivity
- Advanced ceramic materials synthesis
- Molecular Junctions and Nanostructures
- Electrochemical Analysis and Applications
- Advanced Welding Techniques Analysis
Chonnam National University
2016-2025
Sungkyul University
2024
Chonnam National University Hospital
2008-2023
Konyang University
2019-2021
Incheon National University
2020
Gwangju National University of Education
2018
Konyang University Hospital
2002-2017
Yonsei University
2017
Sangmyung University
2014
Catholic University of Korea
2010
The effects of $M$ $(M=\text{Mn},\text{Pr},\text{Sn},\text{Zr})$ doping on the redox thermodynamics ${\text{CeO}}_{2}$ have been investigated using first-principles density-functional theory calculations with on-site Coulomb interaction taken into account. Two different mechanisms for O-vacancy formation in doped clarified. Compared case pure ${\text{CeO}}_{2}$, decrease energy Zr-doped is mostly caused by structural distortion, whereas Mn-, Pr-, or Sn-doped originates from electronic...
Graphene-wrapped lithium-excess layered hybrid materials (Li(2)MnO(3)·LiMO(2), M = Mn, Ni, Co, hereafter abbreviated as LMNCO) have been synthesized and investigated cathode for lithium-ion batteries. Cyclic voltammetry measurement shows a significant reduction of the reaction overpotential in benefit graphene conducting framework. The electrochemical impedance spectroscopy results reveal that can greatly reduce cell resistance, especially charge transfer resistance. Our investigation...
The coupling of oxygen evolution reaction (OER) catalysts with photoanodes is a promising strategy for enhancing the photoelectrochemical (PEC) performance by passivating photoanode's surface defect states and facilitating charge transfer at photoanode/electrolyte interface. However, serious interface recombination issue caused poor OER coating quality often limits further improvement photoanodes. Herein, rapid Fenton-like method demonstrated to produce ultrathin amorphous Ni:FeOOH in...
A facile sol–gel approach combined with a carbon-coating technique via high-temperature thermally decomposing C2H2 has been developed for the synthesis of Li3V2(PO4)3/C (LVP/C) cathode material employing biomass phytic acid as an eco-friendly phosphorus source. The effects on structural, morphological and electrochemical properties LVP have investigated. Compared pristine LVP, LVP/C composite presents higher discharge capacity 127 mA h g−1 at 0.1 C, better rate capability long-term...
An electronically conducting 3D network of reduced graphene oxide (RGO) was introduced into LiNi1/3Mn1/3Co1/3O2 (LNMC) cathode material in a special nano/micro hierarchical structure. The rate test and cycling measurement showed that the networks remarkably improve high performance LNMC electrode for lithium-ion batteries. effect RGO on kinetic property investigated by electrochemical impedance spectroscopy (EIS) potentiostatic intermittent titration (PITT). EIS results reveal greatly...
A general and efficient hydrothermal strategy combined with a high-temperature carbon-coating technique has been developed for large scale synthesis of self-assembled LiFePO4/C nano/microspheres employing the biomass phytic acid as novel eco-friendly phosphorus source. The are investigated by SEM, TEM, EDS, XRD, Raman spectroscopy, electrochemical techniques. reasonable assembly process hierarchical structure is proposed on basis time-dependent experimental results. Because unique structure,...
AgI nanoplates with unusual 7H and 9R polytype phases (see Figure) have been prepared in large quantities by a solution-based method using polyelectrolytes. The exhibit extremely high conductivity, which is enhanced four orders of magnitude compared to the macroscopic phase (β-AgI), surprising conductivity isotropy, both can be explained mesoscopic ionic-conductivity effects heterostructures.
The authors investigate the ion conduction of molecular beam epitaxy grown CaF2∕BaF2 multilayers perpendicular to interfaces. Unlike previous measurements along heterostructure boundaries, more resistive contributions dominate here; detailed analysis allows for a complementary insight into charge carrier distribution. features conductivites in both semi-infinite and mesoscopic situations can be qualitatively as well quantitatively explained by same defect chemical model used parallel...
The authors compared pre-treatment and post-treatment characteristics of 206 prospectively enrolled patients with Kawasaki disease (KD) responsive to intravenous immunoglobulin (IVIG) those 23 (10% total) IVIG non-responders. Demographic were similar in both groups. Compared responders, non-responders had a longer total duration fever higher incidence coronary artery lesions. Prior IVIG, neutrophil differential C-reactive protein, lower cholesterol. 24 hours after the infusion, leucocyte...
The microstructural effects of a Cr-modified Ti–6Al–4V (Ti64) alloy on the mechanical, electrochemical and stress corrosion cracking properties were studied. With aid thermodynamic calculations characterizations, Ti64–3Cr forged was successfully fabricated with no defects by micro-alloying Ti64 3 wt% Cr. microstructure features reveal fine alpha laths lamellar structure strong texturing particularly in basal prismatic poles. mechanical results at room temperature show enhanced yield strength...
The extreme conductivity enhancement (by a factor of up to ) in composites as well the anomalous phase transition α‐phase with large hysteresis 50°C was confirmed by conductivity, differential scanning calorimetry, and situ X‐ray diffractometry (XRD). All exhibited an activation energy 0.29 ± 0.02 eV which identified migration enthalpy for transport disordered close‐packed layers AgI system. A close examination XRD patterns shows existence seven‐layer polytype (7H) stacking sequence ABCBCAC....