A5031793873- 2D Materials and Applications
- Advanced Memory and Neural Computing
- Perovskite Materials and Applications
- Analytical Chemistry and Sensors
- Nanowire Synthesis and Applications
- Concrete Corrosion and Durability
- Smart Materials for Construction
- Gas Sensing Nanomaterials and Sensors
- Physical Unclonable Functions (PUFs) and Hardware Security
- Luminescence and Fluorescent Materials
- Semiconductor materials and devices
- Anodic Oxide Films and Nanostructures
- Nanoporous metals and alloys
- Organic Electronics and Photovoltaics
- Electrowetting and Microfluidic Technologies
- Cell Image Analysis Techniques
- Integrated Circuits and Semiconductor Failure Analysis
- Polyoxometalates: Synthesis and Applications
- Greenhouse Technology and Climate Control
- Quantum Dots Synthesis And Properties
- Water Quality Monitoring Technologies
- Advanced Chemical Sensor Technologies
- Acoustic Wave Resonator Technologies
- Electrocatalysts for Energy Conversion
- Corrosion Behavior and Inhibition
Sungkyunkwan University
2017-2024
University of California, Berkeley
2023-2024
Kookmin University
2019
Materials Science & Engineering
2017
Kyung Hee University
2016
Abstract Since the 4th Industrial Revolution, Internet of Things based environments have been widely used in various fields ranging from mobile to medical devices. Simultaneously, information leakage and hacking risks also increased significantly, secure authentication security systems are constantly required. Physical unclonable functions (PUF) spotlight as an alternative. Chaotic phosphorescent patterns developed on organic crystal atomic seed heterostructure for labels with PUFs....
Plant growth and development are negatively affected by a wide range of external stresses, including water deficits. Especially, plants generally reduce the stomatal aperture to decrease transpiration levels upon drought stress. Advanced technologies, such as wireless communications, Internet things (IoT), smart sensors have been applied practical farming indoor planting systems monitor plants’ signals effectively. In this study, we develop flexible polyimide (PI)-based sensor for real-time...
Physical unclonable functions (PUFs) have attracted interest in demonstrating authentication and cryptographic processes for Internet of Things (IoT) devices. We demonstrated four-dimensional PUFs (4D PUFs) to realize time-varying chaotic phosphorescent randomness on MoS2 atomic seeds. By forming hybrid states involving more than one emitter with distinct lifetimes 4D PUFs, irregular lifetime distribution throughout patterns as a disorder that is impossible replicate. Moreover, we...
MoS2 thin-film transistors (TFTs) are fabricated and simulated to explore the NO2 gas sensing mechanism depending on different device structures. In particular, role of Al2O3 passivation layer channel has been investigated. case nonpassivated TFTs, increase off-current is observed with gas, which modeled modulation effective Schottky barrier height for holes because generation in-gap states near valence band as gases interact channel. The TFTs based nonequilibrium Green's function method,...
Herein, we develop colorimetric multigas sensor arrays assembling chemo-reactive fluorescent patch and 10 × indium gallium zinc oxide phototransistor apply them to an artificial olfactory platform recognize five different volatile organic compounds (VOCs). Porous nanofibers, coupled with two emitters emitting fluorescence, rapidly respond gas-phased VOCs offer unique patterns associated particular gas conditions, including kinds, concentrations, exposure times by forming fluorophore...
We report the enhanced photoresponse in MoS2-MoOx heterojunction thin film structures on SiO2/Si substrates to demonstrate feasibility of using them as highly responsive photodetectors with a wide spectral range from visible near-ultraviolet light. Vertically stacked were obtained through two-step chemical vapor deposition composed MoOx and subsequent sulfurization topmost region as-deposited into MoS2. The formation was revealed by transmission electron microscopy x-ray photoelectron...
A colorimetric multifunctional phototransmittance-based structural durability monitoring system is developed. The consists of an array with four indium gallium zinc oxide (IGZO)-based phototransistors, a light source at wavelength 405 nm through side-emitting optical fiber, and pH- Cl-selective color-variable membranes. Under illumination the corrosion status, Cl-responsive membrane, showing change in their color, generates intensity transmitted light, which received by phototransistor form...
Abstract The thiol‐based functionalization of multilayer MoS 2 is performed to customize its electrical and optical performance. Two types thiol‐terminated organic molecules are utilized: 4‐amino thiophenol (4ATP) for electron‐donating 4‐nitro (4NTP) electron‐withdrawing. thiol groups in these chemically bond with at the sulfur vacancies through simple solution process. 4ATP‐functionalized (4ATP–MoS ) transistors exhibit a huge enhancement current carrier concentration, whereas...
Abstract Broadband photodetectors sensitive to light from visible near‐infrared are essential for various applications such as thermal evaluation, bio‐imaging mapping, and bio‐health monitoring. Multilayer WSe 2 offers broad spectral responses roles in broadband phototransistors’ active matrix. However, it shows relatively lower photoresponsivity than monolayer due layer‐dependent energy band variations. Pentacene islands, a p‐type organic material, formed on the multilayer enhance its under...
Real-time durability monitoring systems in large building structures are an essential technology for smart cities. In this study, a structural-durability health-monitoring (SDHM) system is designed and demonstrated. The SDHM consists of embedded multisensing sensors, data processing modules, subwavelength wideband antenna operating at 900 MHz. sensors reversibly examine the degradation factors inside concrete, possibly offering real-time depth profiles. A ensures stable transmission...
A colorimetric multifunctional sensing method is demonstrated by Hanseung Lee, Sunkook Kim, and co-workers in article number 1807552 for systems to monitor the structural durability-health of buildings. The system consists an array with 4 indium gallium zinc oxide (IGZO)-based phototransistors, a 405 nm light source through side-emitting optical fiber, pH- Cl-selective color-variable membranes. Owing its unique configuration, shows great potential as highly stable sensitive diagnostic tool.
Transition metal dichalcogenides (TMDCs) have shown exceptional optoelectronic properties that can potentially substitute conventional silicon-based devices and be utilized in sensors energy devices. To exploit their wide array of potential applications, it is necessary to develop methods capable on demand, location selective, tunable formation structures arbitrary shape. Here, we demonstrated high-speed direct writing MoSe2 by laser-induced selenization process vacuum or ambient...
<title>Abstract</title> Two-dimensional (2D) semiconductors, such as molybdenum disulfide (MoS2), are emerging key materials for next-generation electronics, addressing challenges in the miniaturization of silicon-based technologies. Despite progress scaling-up 2D materials, integrating them into functional devices remains challenging, particularly context three-dimensional integration. Here, we present a scalable method growing high-quality mono- to few-layer MoS2 on large wafers using...
Efficient light generation from triplet states of organic molecules has been a hot yet demanding topic in academia and the display industry. Herein, we propose strategy for developing emitter by creating heterostructures chromophores transition metal dichalcogenides (TMDs). These emit microsecond phosphorescence at room temperature, while their intrinsically exhibit millisecond under vibration dissipation-free conditions. This enhancement is indicative significantly enhanced spin-orbit...
Abstract Herein, a vertically inverted p–i–n architecture of light‐emitting diodes (LEDs) is designed for manufacturing feasibility and demonstrated scalable bilayer MoS 2 ‐based LEDs. A 4 inch scale prepared by two‐step growth method allocating the pre‐deposition few‐nm thick metal film post‐sulfurization. To apply an active layer in LEDs, transferred over ZnO nanoparticle layers, electron transfer layer, then rest LED components are constructed thermal deposition. This allows individual...
After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in versatile fields of fundamental sciences and industrial applications owing to their periodic arrangement nanopores with relatively high aspect ratio. However, techniques reported so far, which could be only valid for mono-surface show critical disadvantages, i.e., time-consuming as well complicated procedures, requiring toxic chemicals, wasting valuable natural resources. In...
After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in versatile fields of fundamental sciences and industrial applications owing to their periodic arrangement nanopores with relatively high aspect ratio. However, techniques reported so far, which could be only valid for mono-surface show critical disadvantages, i.e., time-consuming as well complicated procedures, requiring toxic chemicals, wasting valuable natural resources. In...
Security Labeling In article 2102542, Dong Hyuk Park, Wook Sunkook Kim, and co-workers demonstrate chaotic phosphorescent patterns based on an organic crystal MoS2 heterostructure for physical unclonable functions (PUFs). Phosphorescent-pattern-based PUFs achieve superior microscale randomness no-cloning code with ease of fabrication. image analysis, encoding capacity as a single PUF domain more than 1017 is achieved 25 μm-cubic sample.