A5084544415- Advanced Thermoelectric Materials and Devices
- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Thermal properties of materials
- Chalcogenide Semiconductor Thin Films
- Graphene research and applications
- Supercapacitor Materials and Fabrication
- Thermal Radiation and Cooling Technologies
- Advanced Battery Technologies Research
- 2D Materials and Applications
- Heusler alloys: electronic and magnetic properties
- Advanced Sensor and Energy Harvesting Materials
- Advanced Thermodynamics and Statistical Mechanics
- Carbon Nanotubes in Composites
- ZnO doping and properties
- Conducting polymers and applications
- Advanced battery technologies research
- Crystallization and Solubility Studies
- Ferroelectric and Piezoelectric Materials
- Advanced Photocatalysis Techniques
- Electrocatalysts for Energy Conversion
- Semiconductor materials and devices
- Nanomaterials and Printing Technologies
- Hydrogen Storage and Materials
- X-ray Diffraction in Crystallography
Kwangwoon University
2019-2025
Ulsan National Institute of Science and Technology
2022-2023
Kyungpook National University
2021
Korea Institute of Ceramic Engineering and Technology
2017-2020
Government of the Republic of Korea
2014-2020
Samsung (South Korea)
2013-2017
Samsung (United States)
2017
Hankyong National University
2017
Stanford University
2015-2016
Korea Advanced Institute of Science and Technology
2006-2014
The widespread use of thermoelectric technology is constrained by a relatively low conversion efficiency the bulk alloys, which evaluated in terms dimensionless figure merit (zT). zT alloys can be improved reducing lattice thermal conductivity through grain boundary and point-defect scattering, target low- high-frequency phonons. Dense dislocation arrays formed at low-energy boundaries liquid-phase compaction Bi(0.5)Sb(1.5)Te3 (bismuth antimony telluride) effectively scatter midfrequency...
Although various carbon nanomaterials including activated carbon, nanotubes, and graphene have been successfully demonstrated for high-performance ultracapacitors, their capacitances need to be improved further wider more challenging applications. Herein, using nitrogen-doped produced by a simple plasma process, we developed ultracapacitors whose (∼280 F/gelectrode) are about 4 times larger than those of pristine based counterparts without sacrificing other essential useful properties...
The increasing demands on high performance energy storage systems have raised a new class of devices, so-called lithium ion capacitors (LICs). As its name says, LIC is an intermediate system between batteries and supercapacitors, designed for taking advantages both types systems. Herein, as quest to improve the Li capability compared that other existing carbon nanomaterials, we developed extrinsically defective multiwall nanotubes by nitrogen-doping. Nitrogen-doped contain wall defects...
Spinel-structured lithium manganese oxide (LiMn2O4) cathodes have been successfully commercialized for various battery applications and are among the strongest candidates emerging large-scale applications. Despite its advantages including high power capability, however, LiMn2O4 chronically suffers from limited cycle life, originating well-known Mn dissolution. An ironical feature with dissolution is that surface orientations supporting Li diffusion thus performance especially vulnerable to...
Most organic radicals possess short lifetimes and quickly undergo dimerization or oxidation. Here, we report on the synthesis by radical templation of a class air- water-stable radicals, trapped within homo[2]catenane composed two rigid fixed cyclobis(paraquat-p-phenylene) rings. The highly energetic octacationic homo[2]catenane, which is capable accepting up to eight electrons, can be configured reversibly, both chemically electrochemically, between each one six experimentally accessible...
Abstract Lithium ion capacitors (LICs) have recently drawn considerable attention because they utilize the advantages of supercapacitors (high power) and lithium batteries energy). However, energy densities conventional LICs, which consist a pair graphite activated carbon electrodes, are limited by small capacities cathodes. To overcome this limitation, we engaged urea‐reduced graphene oxide. The amide functional groups generated during urea reduction facilitate enolization processes for...
Due to its excellent capacity, around 4000 mA h g−1, silicon has been recognized as one of the most promising lithium-ion battery anodes, especially for future large-scale applications including electrical vehicles and utility power grids. Nevertheless, Si suffers from a short cycle life well limitations scalable electrode fabrication. Herein, we report novel design highly robust anodes: nanoparticles embedded in porous nitrogen-doped carbon spheres (NCSs). The nature NCSs buffers volume...
It has been a difficulty to form well-distributed nano- and mesosized inclusions in Bi2Te3-based matrix thereby realizing no degradation of carrier mobility at interfaces between for high thermoelectric performances. Herein, we successfully synthesize multistructured Bi0.4Sb1.6Te3 materials with Fe-rich nanoprecipitates sub-micron FeTe2 by conventional solid-state reaction followed melt-spinning spark plasma sintering that could be facile preparation method scale-up production. This study...
Abstract Point defect or doping in Strontium titanium oxide (STO) largely determines the thermoelectric (TE) properties. So far, insufficient knowledge exists on impact of double Schottky barrier TE performance. Herein, we report a drastic effect performance undoped STO. It demonstrates that incorporation Reduced Graphene Oxide (RGO) into STO weakens and thereby results simultaneous increase both carrier concentration mobility The enhanced exhibits single crystal-like behavior. This boosts...
Our study shows that the H2 storage media using Ni-dispersed fullerenes could be viable alternatives to reversible hydrogen storage. It is demonstrated a single Ni coated on fullerene surface can store up three molecules. Consequently, at high coverage, are considered novel capable of storing ∼6.8wt%H2, thus exceeding Department Energy target (6.5 wt %) for automobile applications. Moreover, desorption activation barrier 11.8kcal∕molH2 ideal many practical
Metal-organic frameworks (MOFs) have recently received much attention as promising candidates for gas storage, chemical separation, and heterogeneous catalysis. However, the applicability of MOFs remains limited due to their relatively large band gaps. Here, on basis first-principles theory study, it is demonstrated that this problem could be overcome by tailoring Zn2+ ions in with Co2+ while maintaining same organic linkers. Density states molecular orbitals two elements, Zn Co ions, show...
Aqueous ammonia absorbent (10 wt %) was modified with four kinds of additives (1 including amine and hydroxyl groups, i.e., 2-amino-2-methyl-1-propanol (AMP), 2-amino-2-methyl-1,3-propandiol (AMPD), 2-amino-2-ethyl-1,3-propandiol (AEPD), tri(hydroxymethyl) aminomethane (THAM), for CO2 capture. The loss by vaporization reduced additives, whereas the removal efficiency slightly improved. These results were attributed to interactions between or absorbents via hydrogen bonding, as verified FT-IR...
Flexible transparent conductive films (TCFs) of TiO2 nanosheet (TiO2 NS) and silver nanowire (Ag NW) network hybrid were prepared through a simple scalable solution-based process. The as-formed NS-Ag NW TCF shows high optical transmittance (TT: 97% (90.2% including plastic substrate)) low sheet resistance (Rs: 40 Ω/sq). In addition, the exhibits long-time chemical/aging electromechanical stability. As for stability, Ag NS reveals retained initial conductivity (ΔRs/Rs < 1%) under ambient...
Lithium ion capacitors (LICs) have recently received considerable attention as a new class of energy storage system because they possess the combined advantages lithium batteries and supercapacitors. LICs typically consist activated carbon cathodes pre-lithiated graphite anodes. Despite promising electrochemical performance, most still hold room for further improvement in terms power density, which is largely related to limited (de)intercalation kinetics graphite. In an attempt address these...
An improved thermoelectric figure of merit (<italic>zT</italic>) 0.14 at 795 K was obtained in 7% Si doped InSe due to the emergence flat band.
Biorefineries are attracting attention as an alternative to the petroleum industry reduce carbon emissions and achieve sustainable development. In particular, because forests play important role in potentially reducing greenhouse gas net zero, alternatives cellulose produced by plants required. Bacterial (BC) can prevent deforestation has a high potential for use biomaterial various industries such food, cosmetics, pharmaceuticals. This study aimed improve BC production from lignocellulose,...
A versatile, facile, and rapid synthetic method of advanced carbon nanotube (CNT)-based nanohybrid fabrication, or the so-called ionic-liquid-assisted sonochemical (ILASM), which combines supramolecular chemistry between ionic liquids (ILs) CNTs with sonochemistry for control in size amount uniformly decorated nanoparticles (NPs) interfacial engineering, is reported. The excellence electrocatalysis hybrid materials well-designed nanostructures favorable interfaces demonstrated by applying...
Octyl formate is an important substance used in the perfume industry products such as cosmetics, perfumes, and flavoring. mostly produced by chemical catalysts. However, using enzymes catalysts has gathered increasing interest due to their environment-friendly proprieties. In present study, we aimed identify optimal conditions for synthesis of octyl through immobilized enzyme-mediated esterification. We investigated effects enzymatic reaction parameters including type enzyme, enzyme...