A5069861371- Graphene research and applications
- Perovskite Materials and Applications
- Advanced Sensor and Energy Harvesting Materials
- Electronic and Structural Properties of Oxides
- Conducting polymers and applications
- Ga2O3 and related materials
- Advancements in Battery Materials
- Semiconductor materials and devices
- 2D Materials and Applications
- Machine Learning in Materials Science
- Advanced Battery Materials and Technologies
- Supercapacitor Materials and Fabrication
- ZnO doping and properties
- Quantum and electron transport phenomena
- Advanced Memory and Neural Computing
- Quantum Dots Synthesis And Properties
- Ferroelectric and Piezoelectric Materials
- Advanced Photocatalysis Techniques
- Fuel Cells and Related Materials
- Electrocatalysts for Energy Conversion
- MXene and MAX Phase Materials
- Thermal properties of materials
- Multiferroics and related materials
- Molecular Junctions and Nanostructures
- Electron and X-Ray Spectroscopy Techniques
Ajou University
2022-2025
Korea Institute of Ceramic Engineering and Technology
2018-2023
Washington University in St. Louis
2018-2021
Hanyang University
2011-2017
Anyang University
2016-2017
MXene has not yet been investigated in optical applications because it is a newly suggested two-dimensional material. In the present work, first investigation of prospects as novel nanodevice was done by applying strain to monolayer Sc2CO2 using first-principles density-functional theory. This single-layer material experiences an indirect direct band gap transition with variation size at relatively small critical about 2%. The work emphasizes that can become promising for modulating...
Abstract High entropy alloys (HEAs) composed of multi‐metal elements in a single crystal structure are attractive for electrocatalysis. However, identifying the complementary functions each element HEAs is prerequisite. Thus, V x CuCoNiFeMn ( = 0, 0.5, and 1.0) investigated to identify active role vanadium improving electrocatalytic activity hydrogen evolution reaction (HER). Structural studies show successful incorporation HEA. 1.0 (V ‐HEA) shows an overpotential 250 mV versus reversible...
Abstract For the application of portable and wearable devices, development energy harvesters sensitive to various types local subtle mechanical displacements is essential. One most abundant but difficult‐to‐harvest energies in everyday life in‐plane kinetic that arises from a rubbing motion. Here, an efficient method proposed generate electrical tiny horizontal forces by laminating microstructures on conventional triboelectric nanogenerator (TENG). The microhairy structures serve induce...
We predict the formation of a polarization-induced two-dimensional electron gas (2DEG) at interface ε-Ga2O3 and CaCO3, wherein density 2DEG can be tuned by reversing spontaneous polarization in ε-Ga2O3, for example, with an applied electric field. is polar metastable ultra-wide band-gap semiconductor. use density-functional theory (DFT) calculations coincidence-site lattice model to region epitaxial strain under which stabilized over its other competing polymorphs suggest promising...
Coil-structured carbon nanotube (CNT) yarns have recently attracted considerable attention. However, structural instability due to heavy twist insertion, and inherent hydrophobicity restrict its wider application. We report a twist-stable hydrophilic coiled CNT yarn produced by the facile electrochemical oxidation (ECO) method. The ECO-treated is prepared applying low potentiostatic voltages (3.0-4.5 V vs Ag/AgCl) between counter electrode immersed in an electrolyte for 10-30 s. Notably,...
Scintillators are widely used for radiation detection in various fields, such as medical imaging, nondestructive testing, and crystallography. X-ray-generating systems typically emit large amounts of heat require a high thermal stability scintillators, particularly testing or performed under harsh conditions. Therefore, highly stable scintillators must be developed application extreme environments. Herein, we new zero-dimensional lead-free monoclinic phases Cs3TbCl6 Rb3TbCl6 metal halides...
In the present paper, band gap characteristics of oxygen functionalized-monolayer scandium carbide (monolayer Sc2CO2) under a perpendicular external electric field (E-field) were studied using DFT calculations for potential application MXene in optoelectronic and optical nanodevices. contrast to general pristine single-layer materials an E-field, monolayer Sc2CO2 undergoes indirect direct transition positive value changes sharply after transition. Remarkable variations properties are induced...
Abstract Transition metal dichalcogenide (TMDCs) alloys could have a wide range of physical and chemical properties, ranging from charge density waves to superconductivity electrochemical activities. While many exciting behaviors unary TMDCs been demonstrated, the vast compositional space TMDC has remained largely unexplored due lack understanding regarding their stability when accommodating different cations or chalcogens in single‐phase. Here, theory‐guided synthesis approach is reported...
We report on the modeling of polarization-induced two-dimensional electron gas (2DEG) formation at ε-AlGaO3/ε-Ga2O3 heterointerface and effect spontaneous polarization (Psp) reversal 2DEG density in ε-Ga2O3/ε-AlGaO3/ε-Ga2O3 double heterostructures. Density-functional theory (DFT) is utilized to calculate material properties ε-Ga2O3 ε-AlGaO3 alloys. Using Schrödinger–Poisson solver along with DFT calculated parameters, as a function barrier type thickness. By optimizing layer thicknesses...
To understand the most intrinsic mechanism of triboelectrification (TE), a straightforward framework TE between metal and single-crystal dielectrics is designed by utilizing both experiments first-principles calculations. Various theoretical models on charge transfer are examined with Interestingly, measured density shows proportional relation interface barrier, which in contrast previous theories. On basis results, backflow-stuck model proposed where determined amount backflow remaining...
Abstract The optimization of traditional electrocatalysts has reached a point where progress is impeded by fundamental physical factors including inherent scaling relations among thermokinetic characteristics different elementary reaction steps, non‐Nernstian behavior, and electronic structure the catalyst. This indicates that currently utilized classes may not be adequate for future needs. study reports on synthesis characterization new class materials based 2D transition metal...
An intimate contact interface between wearable energy harvesting devices and nonflat human surfaces is critical for from the body's movements. The device can only absorb deformation strain under stable interfacial adhesion to biological surfaces. Past developments have mainly examined active layer of such devices, but device/body adhesive effects are rarely considered. Here, we introduce a hierarchically arrayed octopus-inspired pattern (h-OP) formed on piezoelectric composite patch devices....
The comprehensive multiphysics theoretical model on hydrovoltaics shows that the asymmetric protonation gradient and electrokinetic dynamics are key factors for mysterious electricity generation of porous carbons.
Perovskite quantum dots (PQDs) have been considered promising and effective photovoltaic absorber due to their superior optoelectronic properties inherent material merits combining perovskites QDs. However, they exhibit low moisture stability at room humidity (20-30%) owing many surface defect sites generated by inefficient ligand exchange process. These traps must be re-passivated improve both charge transport ability stability. To address this issue, PQD-organic semiconductor hybrid solar...
Bioinspired yarn/fiber structured hydro-actuators have recently attracted significant attention. However, most water-driven mechanical actuators are unsatisfactory because of the slow recovery process and low full-time power density. A rapidly recoverable high-power hydro-actuator is reported by designing biomimetic carbon nanotube (CNT) yarns. The hydrophilic CNT (HCNT) coiled yarn was prepared storing pre-twist into sheets subsequent electrochemical oxidation (ECO) treatment. resulting...
Abstract Tin monoxide (SnO) has been studied widely over the past several decades due to its promising theoretical p‐type performance. However, limited fabrication processes low thermal and air stability of SnO have resulted in poor performance thin‐film transistors (TFTs). Here, it is suggested that situ atomic layer deposition (ALD) an Al 2 O 3 capping can improve electrical TFTs. By adopting stacking process, which protects vulnerable thin films from exposure contamination, exhibits...
The dominant hole transport material (HTM) used in perovskite quantum dot solar cells (PQD-SCs) is a Spiro-OMeTAD, which inevitably requires doping systems to increase charge mobility. However, the use of deliquescent dopants leads degradation PQD-SCs, necessitating development efficient dopant-free HTMs for their commercialization. Here, we designed three types HTMs: Asy-PDTS, Asy-PSDTS, and Asy-PSeDTS. We apply chalcogenide-based fluorinated benzothiadiazole as rigid segment acceptor unit...
Triboelectrification mechanism is still not understood, despite centuries of investigations. Here, we propose a model showing that mechanochemistry key to elucidate triboelectrification fundamental properties. Studying contact between gold and silicate glasses, observe the experimental triboelectric output subject large variations polarity inversions. First principles analysis shows electronic transfer activated by tribopolarity determined termination exposed contact, depending on material...
Abstract Graphdiyne (GDY) has garnered significant attention as a cutting‐edge 2D material owing to its distinctive electronic, optoelectronic, and mechanical properties, including high mobility, direct bandgap, remarkable flexibility. One of the key challenges hindering implementation this in flexible applications is large area uniform synthesis. The facile growth centimeter‐scale bilayer hydrogen substituted graphdiyne (Bi‐HsGDY) on germanium (Ge) substrate achieved using low‐temperature...
This study addresses the optimization of strain in continuous MOSFET downscaling, particularly at nanoscale, where traditional Fourier models fail due to non-diffusive phonon transport effects. We introduce a multi-physics simulation approach that combines Finite Element Method (FEM) and Density Functional Theory (DFT) calculations design strain-optimized 3D structures. By implementing kinetic collective model within FEM simulations, we accurately predict thermal-induced strains Si channel...
Understanding the mechanism underlying triboelectrification (TE) in polymers is crucial for developing cheap and effective triboelectric nanogenerators. Finding out how a polymer becomes tribopositive especially relevant, as most tend to charge negatively, reducing power output range of applications. Thus far, it has remained unclear whether TE be attributed homolytic ion transfer, heterolytic material or electronic transfer. Investigating polyoxymethylene by first-principle investigations,...
Quantum-confined lead-halide perovskite nanocrystals (QPNCs) are a promising optoelectronic semiconductor owing to their exceptional fluorescence and the size- dimension-tunable optical properties. QPNCs having low formation energy encounter challenges in accurately regulating nucleation crystal growth stages during injection-based syntheses using lead halide reagents. Here, we introduce non-injection, one-pot synthetic approach based on bimolecular nucleophilic substitution (SN2)...