A5100618958- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Advanced battery technologies research
- Graphene research and applications
- Conducting polymers and applications
- Electrocatalysts for Energy Conversion
- Quantum Dots Synthesis And Properties
- Carbon Nanotubes in Composites
- Advanced Battery Technologies Research
- Supercapacitor Materials and Fabrication
- Graphene and Nanomaterials Applications
- X-ray Diffraction in Crystallography
- Chalcogenide Semiconductor Thin Films
- Semiconductor materials and devices
- Ammonia Synthesis and Nitrogen Reduction
- Diamond and Carbon-based Materials Research
- Nanowire Synthesis and Applications
- Covalent Organic Framework Applications
- Advanced Fiber Laser Technologies
- Nanofabrication and Lithography Techniques
- Crystallization and Solubility Studies
- Photonic and Optical Devices
- Organic Electronics and Photovoltaics
- ZnO doping and properties
- Advanced Fiber Optic Sensors
Ulsan National Institute of Science and Technology
2018-2025
The Ohio State University
2024-2025
Korea Institute of Science and Technology
2013-2023
Korea Institute of Industrial Technology
2023
Inha University
2022
Pohang University of Science and Technology
2022
Sungkyunkwan University
2021
Government of the Republic of Korea
2020
Myongji University
2019-2020
Yong In University
2019
We experimentally demonstrate a femtosecond mode-locked, all-fiberized laser that operates in the 2 μm region and incorporates saturable absorber based on bulk-structured bismuth telluride (Bi(2)Te(3)) topological insulator (TI). Our fiberized was prepared by depositing mechanically exfoliated, ~30 μm-thick Bi(2)Te(3) TI layer side-polished optical fiber platform. The bulk crystalline structure of confirmed Raman X-ray photoelectron spectroscopy measurements. modulation depth measured to be...
Abstract Chlorine evolution reaction (CER) is a critical anode in chlor-alkali electrolysis. Although precious metal-based mixed metal oxides (MMOs) have been widely used as CER catalysts, they suffer from the concomitant generation of oxygen during CER. Herein, we demonstrate that atomically dispersed Pt−N 4 sites doped on carbon nanotube (Pt 1 /CNT) can catalyse with excellent activity and selectivity. The Pt /CNT catalyst shows superior to nanoparticle-based commercial Ru/Ir-based MMO...
Abstract Understanding the local cation order in crystal structure and its correlation with electrochemical performances has advanced development of high‐energy Mn‐rich cathode materials for Li‐ion batteries, notably Li‐ layered cathodes (LMR, e.g., Li 1.2 Ni 0.13 Mn 0.54 Co O 2 ) that are considered as nanocomposite C2/m MnO 3 ‐type medium‐range (MRO). Moreover, Li‐transport rate high‐capacity Mn‐based disordered rock‐salt (DRX) (e.g., 0.4 Ti is found to be influenced by short‐range...
Abstract Out of practicality, ambient air rather than oxygen is preferred as a fuel in electrochemical systems, but CO 2 and H O present cause severe irreversible reactions, such the formation carbonates hydroxides, which typically degrades performance. Herein, we report on Na-air battery enabled by reversible carbonate reaction (Na 3 ·xH O, x = 0 or 1) Nasicon solid electrolyte Zr Si PO 12 ) that delivers much higher discharge potential 3.4 V other metal-air batteries resulting high energy...
Abstract Ordered mesoporous carbons (OMCs) have attracted considerable interest owing to their broad utility. OMCs reported date comprise amorphous rod‐like or tubular graphitic frameworks, which exhibit tradeoffs between conductivity and surface area. Here we report ordered constructed with frameworks (OMGCs) tunable pore sizes mesostructures via dual templating, using silica molybdenum carbide as exo ‐ endo ‐templates, respectively. OMGCs simultaneously realize high electrical large area...
This paper presents a charge-domain in-memory computing (IMC) macro for precision-scalable deep neural network accelerators. The proposed Dual-SRAM cell structure with coupling capacitors enables multiply and accumulate (MAC) operation variable-precision signed weights. Unlike prior IMC macros that only support binary networks or digitally compute weighted sums MAC multi-bit weights, the implements analog energy-efficient bit-scalable operations novel series-coupled merging scheme. A test...
Highly luminescent quantum dots with a reverse type-I core/shell/shell structure consisting of ZnSe/InP/ZnS are developed. Their emission color can be tuned from violet to red by controlling the InP shell thickness. The final layer ZnS improves yield.
Abstract Hydrogen flow during low pressure chemical vapor deposition had significant effect not only on the physical properties but also electrical of graphene. Nucleation and grain growth graphene increased at higher hydrogen flows. And, more oxygen-related functional groups like amorphous oxidized carbon that probably contributed to defects or contamination remained surface H 2 conditions. It is believed flow, those oxygen other oxidizing impurities make films p-doped result in decreasing...
Abstract Conducting polymer‐based organic electrochemical capacitor materials have attracted attention because of their highly conductive nature and reversible redox reactions on the surface electrodes. However, owing to poor stabilities in aprotic electrolytes, alternative capacitive electrodes are being actively sought. Here, fluorine atoms introduced into contorted hexabenzocoronene (cHBC) achieve first small‐molecule‐based energy‐storage cells that operate at high current rates with...
Deactivated current collector surface for reliable seawater battery.
It is widely known that semiconductors such as ZnO and ZnS tend to be unstable in water-splitting photocatalysis due self-corrosion by the photogenerated charges under prolonged light irradiation. In this work, we demonstrate proper engineering of photodeposition Rh species on ZnO–ZnS heterostructure (ZnO/ZnS) can enhance their photocatalytic activity secure stability at same time. During photodeposition, both electrons holes generated surface ZnO/ZnS contributed formation Rh0 metal...
Benzo[c]cinnoline (1) is investigated as a low-potential organic anode material for alkaline aqueous batteries (AABs). As materials are typically poor catalysts hydrogen evolution reaction (HER), prepared with 1 can significantly reduce the rate of production and self-discharge, common issue conventional metal hydride anodes. Galvanostatic charge–discharge tests paired Ni(OH)2 cathode in an electrolyte (4 M KOH + 2 KF K2CO3) show cell voltage 1.3 V capacity 229 mAh g–1, negligible fading...
Organic anode materials have garnered attention for use in rechargeable Li-ion batteries (LIBs) owing to their lightweight, cost-effectiveness, and tunable properties. However, challenges such as high electrolyte solubility limited conductivity, restrict full-cell LIBs. Here, we report the of highly crystalline Cl-substituted contorted hexabenzocoronene (Cl-cHBC) an efficient organic By employing antisolvent crystallization method, crystallinity Cl-cHBC has been significantly enhanced,...
Apart from conventional redox chemistries, exploring high-voltage anionic processes, such as pure oxygen or high-valent transition metal ion redox, poses challenges due to the instability of O nonbonding O-dominant energy states. These states are associated with destructive behaviors in layered oxide cathodes, including local structural distortion, cationic disordering, and gas evolution. In this study, we suppress first-cycle voltage hysteresis irreversible 2 evolution Li-rich cathodes...
The electrochemical nitrogen (N 2 ) reduction reaction (eNRR) is pivotal for synthesizing green ammonia (NH 3 under ambient conditions. However, challenges such as mitigating the detrimental hydrogen evolution (HER) and overcoming the...
Although development and utilization of efficient catalysts with earth-abundant cheap elements are desired, precious noble metal-based still widely used studied due to the urgent need address energy environmental issues. Polyoxometalates (POMs) can be excellent candidates in this context. In study, we found that oxo-bridged tetraruthenium polyoxometalate (RuPOM) exhibits electrocatalytic activity for both oxygen evolution reduction reactions (OER ORR) minimal use metal seawater batteries...
Contorted hexabenzocoronene molecule as a promising Li insertion organic anode.
Abstract In this work, a highly conductive organic cocrystal is investigated as an anode material for conducting agent‐free lithium‐ion battery (LIB) electrodes. A unique morphology of semiconducting fullerene (C 60 ) and contorted hexabenzocoronene (cHBC) developed that efficiently enhances the electron transfer during discharge charge processes due to formation well‐defined junction between C cHBC. particular, present study reveals exact phase orthorhombic Pnnm using grazing incidence...
Sodium-metal-based seawater batteries (SWB) are considered an attractive energy storage system because of the cost-effective nature Na+ ions. However, high overpotential and low power output caused by limitations cathode material have impeded their commercialization. To overcome these injurious issues, herein we report enhanced oxygen reduction reaction (ORR)/oxygen evolution (OER) activities SWBs using a well-controlled N-doped carbon cloth as current collector. The resulting...