A5101678699- Graphene research and applications
- Advanced Photocatalysis Techniques
- TiO2 Photocatalysis and Solar Cells
- Catalytic Processes in Materials Science
- ZnO doping and properties
- Material Dynamics and Properties
- Nanowire Synthesis and Applications
- Protein Structure and Dynamics
- Carbon Nanotubes in Composites
- Machine Learning in Materials Science
- CO2 Reduction Techniques and Catalysts
- Gold and Silver Nanoparticles Synthesis and Applications
- Semiconductor materials and devices
- Advanced Sensor and Energy Harvesting Materials
- Supercapacitor Materials and Fabrication
- Ferroelectric and Piezoelectric Materials
- Spectroscopy and Quantum Chemical Studies
- Electrocatalysts for Energy Conversion
- Advanced Nanomaterials in Catalysis
- GaN-based semiconductor devices and materials
- Nuclear Materials and Properties
- Copper-based nanomaterials and applications
- Acoustic Wave Resonator Technologies
- Silicon Nanostructures and Photoluminescence
- Enzyme Structure and Function
Washington University in St. Louis
2024-2025
Korea Institute of Science and Technology
2009-2024
Korea University of Science and Technology
2023-2024
Massachusetts Institute of Technology
2008-2023
Hongik University
2018-2022
Korea Institute of Energy Research
2012-2020
Government of the Republic of Korea
2014
Seoul National University
1995-2012
University of Maryland, College Park
2009
NIST Center for Neutron Research
2009
Recent advances in flexible and stretchable electronics have led to a surge of electronic skin (e-skin)-based health monitoring platforms. Conventional wireless e-skins rely on rigid integrated circuit chips that compromise the overall flexibility consume considerable power. Chip-less based inductor-capacitor resonators are limited mechanical sensors with low sensitivities. We report chip-less e-skin surface acoustic wave made freestanding ultrathin single-crystalline piezoelectric gallium...
Electrostatic capacitors are foundational components of advanced electronics and high-power electrical systems owing to their ultrafast charging-discharging capability. Ferroelectric materials offer high maximum polarization, but remnant polarization has hindered effective deployment in energy storage applications. Previous methodologies have encountered problems because the deteriorated crystallinity ferroelectric materials. We introduce an approach control relaxation time using...
This paper reports an approach to repurpose low-cost, bulk multilayer MoS2 for development of ultraefficient hydrogen evolution reaction (HER) catalysts over large areas (>cm2). We create working electrodes use in HER by dry transfer nano- and microflakes gold thin films deposited on prestrained thermoplastic substrates. By relieving the prestrain at a macroscopic scale, tunable level tensile strain is developed consequently results local phase transition as result spontaneously formed...
Free-standing crystalline membranes are highly desirable owing to recent developments in heterogeneous integration of dissimilar materials. Van der Waals (vdW) epitaxy enables the release from their substrates. However, suppressed nucleation density due low surface energy has been a challenge for crystallization; reactive materials synthesis environments can induce detrimental damage vdW surfaces, often leading failures membrane release. This work demonstrates novel platform based on...
A super-Arrhenius-to-Arrhenius dynamic crossover phenomenon has been observed in the translational α-relaxation time and inverse of self-diffusion constant both experimentally by simulations for lysozyme hydration water temperature range TL = 223 ± 2 K. MD are based on a realistic hydrated powder model, which uses TIP4P-Ew rigid molecular model water. The convergence neutron scattering, nuclear magnetic resonance dynamics supports interpretation that this is result gradual evolution...
Proton nuclear magnetic resonance (1H NMR) experiments have been performed to measure the spin−lattice, T1, and spin−spin, T2, relaxation times of three functional groups in water/methanol mixtures at different methanol molar fractions (XMeOH = 0, 0.04, 0.1, 0.24, 0.5, 1) as a function temperature range 205 K < T 295 K. The measured mixtures, all fractions, are faster than those pure water because strong interactions, resulting complex hydrogen bonding dynamics that determines their...
Graphene (GR) exhibits impressive photoelectric properties, including a large specific surface area, high charge-carrier mobility, conductance, and fast electron transfer. In this study, the effect of GR on performance dye-sensitized solar cells (DSSCs) was investigated by mixing into N-doped TiO2 photoelectrodes. GR/N-doped (GNT) nanoparticles were prepared using sol–gel method. After preparation, presence in photoelectrodes confirmed transmission microscopy (TEM), X-ray diffraction (XRD),...
Abstract The optimization of nanomaterial synthesis using numerous synthetic variables is considered to be an extremely laborious task because conventional combinatorial explorations are prohibitively expensive. In this work, autonomous experimentation platform developed for the bespoke design metal nanoparticles (NPs) with targeted optical properties reported. This operates in a closed‐loop manner between batch module NPs and UV–vis spectroscopy module, based on feedback AI modeling. With...
Abstract Inexpensive, high‐speed deposition techniques that ensure uniformity, scalability, wide applicability, and tunable thickness are crucial for the practical application of 2D materials. In this work, rapid drying is identified as a key mechanism pioneering two wet methods: hot dipping air knife sweeping (AKS). Both allow control proportional to flake concentration, achieving tiled monolayers pinhole‐free coverage across entire substrate, long evaporation outpaces diffusion. AKS...
Studies on the influence of environmental temperature pathogenesis rabies in two species experimentally infected Chiroptera, Mexican free-tailed bat (Tadarida mexicana) and little brown (Myotis lucifugus), provided evidence that or no viral multiplication occurs inactive host during induced hibernation. When inoculated animals are wakened from hibernation by transfer to a warm room, virus previously "cold storage" multiplies, reaching detectable levels various tissues. Similar results were...
In this study, the effect of Zr doping on performance dye-sensitized solar cells (DSSCs) based Zr/N-doped TiO2 photoelectrodes was investigated. nanoparticles were synthesized with various contents using sol–gel method. The had high surface areas, uniform particle sizes, and a strong red shift their absorption into visible region as compared P25 nanoparticles. DSSCs fabricated 0.01 M photoelectrode achieved maximum power conversion efficiency 12.62% short-circuit current (Jsc) 26.37 mA cm−2,...
The low-temperature behavior of proteins under high pressure is not as extensively investigated that at ambient pressure. In this paper, we study the dynamics a hydrated protein moderately pressures low temperatures using quasielastic neutron scattering method. We show when applying to protein−water system, hydration water does slow down but becomes faster instead. degree "softness" protein, which intimately related enzymatic activity shows same trend its function temperature different...
Interactions of various ligands and receptors have been extensively investigated because they regulate a series signal transduction leading to functional cellular outcomes. The on cell membrane recognize their specific ligands, resulting in binding between receptors. Accumulating evidence reveals that the difference spatial characteristics as well types ligands. Thus, control multiple presented therapeutic nanoparticles is believed impact functions. Specifically, localized multivalent...
This review article describes our neutron scattering experiments made in the past four years for understanding of single-particle (hydrogen atom) dynamics a protein and its hydration water strong coupling between them. We found that key to this is existence fragile-to-strong dynamic crossover (FSC) phenomenon occurring at around TL = 225±5 K water. On lowering temperature toward FSC, structure makes transition from predominantly high density form (HDL), more fluid state, low (LDL), less...
Electronic density of states (DOS) is a key factor in condensed matter physics and material science that determines the properties metals. First-principles density-functional theory (DFT) calculations have typically been used to obtain DOS despite considerable computation cost. Herein, we report fast pattern learning method for predicting patterns not only bulk structures but also surface multi-component alloy systems by principal component analysis. Within this framework, use four features...