A5081397810- 2D Materials and Applications
- Perovskite Materials and Applications
- Quantum Dots Synthesis And Properties
- MXene and MAX Phase Materials
- CCD and CMOS Imaging Sensors
- Nanowire Synthesis and Applications
- Molten salt chemistry and electrochemical processes
- Graphene research and applications
- Chalcogenide Semiconductor Thin Films
- Photonic and Optical Devices
- Nuclear materials and radiation effects
- Nuclear Materials and Properties
- Image Processing Techniques and Applications
- Conducting polymers and applications
- Advanced Memory and Neural Computing
- Advancements in Battery Materials
- Neural Networks and Reservoir Computing
- Photoacoustic and Ultrasonic Imaging
- Electrocatalysts for Energy Conversion
- Spectroscopy Techniques in Biomedical and Chemical Research
- Precipitation Measurement and Analysis
- Infrared Target Detection Methodologies
- Plasmonic and Surface Plasmon Research
- Modular Robots and Swarm Intelligence
- Advanced Semiconductor Detectors and Materials
Seoul National University of Science and Technology
2023-2025
University of Applied Sciences Technikum Wien
2023
TU Wien
2021-2023
Daegu Gyeongbuk Institute of Science and Technology
2014-2022
Government of the Republic of Korea
2015-2016
Daegu University
2016
Chonnam National University
2013
We demonstrate a highly sensitive hybrid photodetector based on graphene–CsPbBr<sub>3−x</sub>I<sub>x</sub> perovskite nanocrystals.
Optical spectroscopy is an indispensable technique in almost all areas of scientific research and industrial applications. After its acquisition, optical spectrum usually further processed using a mathematical algorithm to classify or quantify the measurement results. Here we present design realization smart photodetector that provides such information directly without need explicitly record spectrum. This achieved by tailoring spectral responsivity device specific purpose. In-sensor...
High-sensitivity photodetectors are reported using solution synthesized GeS and GeSe nanosheets.
Zero-dimensional-two-dimensional (0D-2D) hybrid optoelectronic devices have demonstrated high sensitivity and performance due to the absorption coefficient of 0D materials with a tunable detection range carrier transport property 2D materials. However, reported 0D-2D employ toxic nanomaterials as sensitizing layers, which can limit practical applications. In this study, we first fabricated photodetector using nontoxic InP quantum dots (QDs) light-absorbing layer black phosphorus (BP) layer....
2-Dimensional (2D) and 0-dimensional (0D) hybrid nanostructures have been reported as promising new systems for highly-sensitive wavelength-tunable photodetectors. Although the performance of photodetectors was enhanced by charge injection from 0D nanocrystals (NCs) to 2D nanosheets (NSs), response time is still very slow due trapping leakage residual carriers at interfaces materials. Here, we demonstrate a MoS2/CdSe phototransistor with responsivity 2.5 × 105 A W−1 detectivity 1.24 1014...
While 2D transition metal dichalcogenides (TMDs) are promising building blocks for various optoelectronic applications, limitations remain multilayered TMD-based photodetectors: an indirect bandgap and a short carrier lifetime by strongly bound excitons. Accordingly, TMDs with direct enhanced required the development of devices. Here, periodically arrayed nanopore structures (PANS) proposed improving efficiency p-WSe2 /n-MoS2 phototransistors. Density functional theory calculations as well...
Abstract The quasi‐2D perovskite family, PEA₂(FA 0.7 Cs 0.3 ) n‐1 Pb n Br₃ n+1 ( = 2, 3, …, ∞), has emerged as an efficient emission layer for next‐generation light‐emitting diodes (PeLEDs) due to its self‐aligned multi‐quantum well structure of mixed phases, facilitating energy transfer from lower higher n‐phases compared bulk perovskites. However, despite their advantageous characteristics, perovskites have suffered efficiency and stability issues. During the formation films, internal...
Abstract Cs 3 Cu 2 X 5 ‐based lead‐free material (X = Cl, Br, and I) nanocrystals (NCs) are promising eco‐friendly materials for various optoelectronic applications. Although manganese (Mn 2+ ) ion doping into may widen the emission color gamut, incorporating them is challenging because of robust tetrahedral [CuX 4 ] triangular structures. This paper addresses this challenge using a lattice engineering strategy, which induces appropriate shrinkage by replacing I − with Cl in NC structure....
Abstract By using first principles DFT calculations, we reveal oxygen reduction reaction mechanisms in N‐doped graphene (N‐Gr). Considering both the morphology and concentration of dopant N atoms bulk edge N‐Gr forms, calculate energies a large number model systems to cover wide range possible structures determine most stable forms. In agreement with experiments, our calculations suggest that doping levels forms are limited less than approximately 30 at. % N, above which hexagonal framework...
Two-dimensional black phosphorus (BP) has attracted much attention recently because of its applicability in high-performance electronic and optoelectronic devices. BP field-effect transistors (FETs) with a tunable band gap (0.3–1.5 eV) have demonstrated high on–off current ratio hole mobility an ambipolar behavior global-gated However, local-gated FETs for integrated circuits been reported only p-type behaviors low on-current compared FETs. Furthermore, BP, which is not stable air, forms...
Few-layer black phosphorus (BP) has shown great potential for next-generation electronics with tunable band gap and high carrier mobility. For the electronic applications, thickness modulation of a BP flake is essential due to its thickness-dependent properties. However, controlling precise few-layer challenge high-performance device applications. In this study, we demonstrate that thermal treatment under ambient condition precisely controls flake. The etching method utilizes chemical...
Recently, black phosphorus (BP) with direct band gap exhibited excellent potential for optoelectronic applications because of its high charge carrier mobility and low dark current as well the variable 0.3-1.5 eV depending on number layers. However, few-layer BP-based phototransistors (photo-FETs) have been limited in sensitivity wavelength selectivity. To overcome drawback these photo-FETs, we studied hybrid photo-FETs combined novel properties two materials between channel sensitizer By...
Abstract 2D van der Waals materials are promising for various electronic and optoelectronic devices because of their thickness‐dependent mobility tunable bandgap. Recently, heterojunction structures based on have exhibited potential photovoltaic applications as ultrathin p–n diodes. In this study, the effect a multilayer black phosphorus (BP)/WS 2 device is demonstrated under 405 nm laser illumination AM 1.5 solar spectrum. The diode‐like characteristics rely balance between charge carriers...
Abstract Black phosphorus (BP) has drawn enormous attention for both intriguing material characteristics and electronic optoelectronic applications. In spite of excellent advantages semiconductor device applications, the performance BP devices is hampered by formation oxide on surface under ambient conditions. It thus necessary to resolve oxygen‐induced degradation recover stability devices. To solve this problem, it demonstrated that a 1,2‐ethanedithiol (EDT) treatment simple effective way...
Abstract Pixel binning is a technique, widely used in optical image acquisition and spectroscopy, which adjacent detector elements of an sensor are combined into larger pixels. This reduces the amount data to be processed as well impact noise, but comes at cost loss information. Here, we push concept its limit by combining large fraction single “superpixel” that extends over whole face chip. For given pattern recognition task, optimal shape determined from training using machine learning...
Recently, metal halide perovskite nanocrystals have demonstrated outstanding properties in various optoelectronic applications. Cesium lead halides (CsPbX3) are the most studied perovskites nanoscale dimensions. However, with other cations rarely been reported. It is important to develop new compositions further expand their application fields. In this paper, we first report synthesis of colloidal rubidium iodide (RbPbI3) nanowires (NWs). RbPbI3 NWs an orthorhombic crystal structure and...
Abstract Semiconductor p–n junctions are building blocks for optoelectronic devices. Recently, junction devices based on 2D transition metal dichalcogenides (TMDCs) have been demonstrated in applications due to their thin thickness, flexibility, high carrier mobility, and light‐absorption properties. To fabricate semiconductor devices, various methods demonstrated, such as heterojunction structures, chemical doping, electrostatic doping. In this work, lateral both n–p WSe 2 electrically...
We report a new family of inorganic ligands, namely, transition metal-based thiometallates, for the surface functionalization colloidal nanocrystals (NCs). synthesized Pt-, Fe-, Co-, and Ni-based in which metal ions were complexed with polysulfides. These anions easily exchanged organic ligands various metal, semiconductor, oxide materials, without affecting NCs' primary structural optical characteristics. Furthermore, upon heating, these complexes decomposed transformed into crystalline...
Abstract The high‐speed modulation of the nanoscale light sources is fundamental interest in nanophotonics. Here, electrically driven emission from a metal–insulator–semiconductor heterostructure consisting graphene, hexagonal boron nitride (h‐BN), and monolayer tungsten disulfide (WS 2 ) demonstrated. Electroluminescence these devices originates radiative recombination majority carriers (electrons) accumulated by electrostatic doping hot minority (holes) injected into WS graphene through an...