A5070144297- Graphene research and applications
- Molecular Junctions and Nanostructures
- Advanced Photocatalysis Techniques
- 2D Materials and Applications
- Electrocatalysts for Energy Conversion
- Advanced Memory and Neural Computing
- Quantum and electron transport phenomena
- Gas Sensing Nanomaterials and Sensors
- Advanced battery technologies research
- Quantum Dots Synthesis And Properties
- Advancements in Battery Materials
- Perovskite Materials and Applications
- Electrochemical Analysis and Applications
- Graphene and Nanomaterials Applications
- Advanced Sensor and Energy Harvesting Materials
- TiO2 Photocatalysis and Solar Cells
- Catalytic Processes in Materials Science
- Supercapacitor Materials and Fabrication
- Surface and Thin Film Phenomena
- Conducting polymers and applications
- Nanowire Synthesis and Applications
- MXene and MAX Phase Materials
- Advanced Nanomaterials in Catalysis
- Transition Metal Oxide Nanomaterials
- Electronic and Structural Properties of Oxides
Sungkyunkwan University
2014-2024
Institute for Basic Science
2017-2024
Government of the Republic of Korea
2020
Samsung (South Korea)
2008-2012
Chonnam National University
2012
Supercapacitors with porous carbon structures have high energy storage capacity. However, the nature of electrode, composed mainly nanotubes (CNTs) and graphene oxide (GO) derivatives, negatively impacts volumetric electrochemical characteristics supercapacitors because poor packing density (<0.5 g cm(-3)). Herein, we report a simple method to fabricate highly dense vertically aligned reduced (VArGO) electrodes involving hand-rolling cutting processes. Because their opened-edge structure,...
A novel memory cell structure with a Pt/Ti-doped NiO/Pt architecture is shown to exhibit the lowest write current reported thus far for unipolar switching resistance-change-based device, as in figure. The decreases dramatically upon scaling sizes smaller than 100 nm×100 nm. High-density universal can be fabricated by combining this node element selective switch.
Nonvolatile memory devices using gold nanoparticles (AuNPs) and reduced graphene oxide (rGO) sheets were fabricated in both horizontal vertical structures. The device, which a singly doubly overlayered semiconducting rGO channel was formed by simply spin-casting technique to connect two electrodes, designed for understanding the origin of charging effects. AuNPs chemically bound through π-conjugated molecular linker. bifunctional linker, 4-mercapto-benzenediazonium tetrafluoroborate (MBDT)...
We report on the interlayer screening effect of graphene using Kelvin probe force microscopy (KPFM). By a gate device configuration that enables supply electronic carriers in sheets, vertical properties were studied from measuring surface potential gradient. The results show layer-dependence as number layers increases, decreases exponentially. In addition, we calculate work function-related information KPFM.
A strong electrostatic MV2+-GQD nanocomposite provides an electrolyte-free flexible electrochromic device wih high durability. The positively charged MV2+ and negatively GQD are strongly stabilized by non-covalent intermolecular forces (e.g., interactions, π–π stacking cation-π electron interactions), eliminating the need for electrolyte. An fabricated from GQD-supported exhibits stable performance under mechanical thermal stresses. As a service to our authors readers, this journal...
We introduce non-volatile resistive crossbar memory based on ionic liquid covalently functionalized a partially reduced graphene oxide (PrGO). The write-read-erase-read (WRER) cycles were very stable after several hundred and the retention time of both ON OFF states was for over 1000 s, indicating that device we developed can function as device.
As memory materials, two-dimensional (2D) carbon materials such as graphene oxide (GO)-based have attracted attention due to a variety of advantageous attributes, including their solution-processability and potential for highly scalable device fabrication transistor-based cross-bar arrays. In spite this, the use GO-based has been limited, primarily uncontrollable oxygen functional groups. To induce stable effect by ionic charges negatively charged carboxylic acid group partially reduced...
Effective charge separation and rapid transport of photogenerated carriers without self-oxidation in transition metal dichalcogenide photocatalysts are required for highly efficient stable hydrogen generation. Here, we report that a molecular junction as an electron transfer path toward two-dimensional rhenium disulfide (2D ReS2) nanosheets from zero-dimensional titanium dioxide (0D TiO2) nanoparticles induces high efficiency stability solar generation by balanced carriers. The junctions...
Graphdiyne (GDY), a new 2D material, has recently proven excellent performance in photodetector applications due to its direct bandgap and high mobility. Different from the zero-gap of graphene, these preeminent properties made GDY emerge as rising star for solving bottleneck graphene-based inefficient heterojunction. Herein, highly effective graphdiyne/molybdenum (GDY/MoS2 ) type-II heterojunction charge separation is reported toward high-performance photodetector. Characterized by robust...
Reduction to the essential: A highly conductive and soft carbon interlayer of reduced graphene oxide (rGO) prevents formation a filamentary current path, achieving both high yield true molecular effects in monolayer-based devices. Junctions rGO contacts with monolayers elucidate molecularly resolved electronic properties resistors nonvolatile memories. Detailed facts importance specialist readers are published as "Supporting Information". Such documents peer-reviewed, but not copy-edited or...
A major challenge in the development of electrocatalysts is to determine a detailed catalysis mechanism on molecular level for enhancing catalytic activity. Here, we present bottom-up studies an electrocatalytic hydrogen evolution reaction (HER) process through activation systematically control surface activity corresponding interfacial charge transfer porphyrin monolayer inactive graphene. The two-dimensional (2D) assembly porphyrins that create homogeneous active sites (e.g.,...
The solution-processed fabrication of an azobenzene (ABC10) monolayer-based nonvolatile memory device on a reduced graphene oxide (rGO) electrode is successfully accomplished. Trans-–cis isomerizations ABC10 between two rGO electrodes in crossbar are controlled by applied voltage. An soft-contact top plays important role the conformational-change-dependent conductance switching process monolayer.
Research into the development of efficient semiconductor photocatalytic materials is a promising approach to solving environmental and energy problems worldwide. Among these materials, TiO2 photocatalysts are one most commonly used due their photoactivity, high stability, low cost friendliness. However, since UV content sunlight less than 5%, visible light-activated TiO2-based essential increase solar efficiency. Here, we review recent works on advanced Ti3+-self-doped (Ti3+–TiO2) with...
A simple chemical method to obtain bulk quantities of N-doped, reduced graphene oxide (rGO) sheets (see figure) as an n-type semiconductor through the treatment as-prepared GO with commonly used reducing reagent hydrazine, followed by rapid thermal annealing (RTA) is described.
Currently, most carbon monoxide (CO) gas sensors work at high temperatures of over 150 °C. Developing CO that operate room temperature is challenging because the sensitivity trade-offs. Here, we report an ultrasensitive sensor using fluorine-graphdiyne (F-GDY) in which electrons are increased by light. The GDY films used as channels field-effect transistors were prepared chemical vapor deposition and characterized various spectroscopic techniques. With exposure to UV light, F-GDY showed a...
Photocatalytic removal of indoor organic air pollutants is effective, but there are practical limits to catalytic activation by conditions. Here, we report a molecular-linked heterojunction semiconducting metal oxide nanoparticles (e.g., Blue TiO2 and WO3) that can be activated wide-range light including an light-emitting diode (LED) under ambient Chemically reduced improves visible absorption white regulating the electronic structure with self-doping Ti3+. The between WO3 formed via...
Play the field: A field-effect transistor using reduced graphene oxides was prepared through reduction of connected between two electrodes. The use pyrene with an electron-withdrawing group and electron-donating showed p- n-doping effects, respectively, while backbone no or -donating groups doping effect. Detailed facts importance to specialist readers are published as "Supporting Information". Such documents peer-reviewed, but not copy-edited typeset. They made available submitted by...
Synthesis of graphene nanostructures has been investigated to provide outstanding properties for various applications. Herein, we report molecular thin film-assisted growth into nanofeatures such as nanoribbons and nanoporous sheets along with a predetermined orientation on dielectric substrates without metal catalysts. A Langmuir-Blodgett (LB) method was used the formation molecularly patterned SiO2 ferric stearate layers, which acted template directional polypyrrole precursor. The were...
Thermally doped nitrogen atoms on the sp(2)-carbon network of reduced graphene oxide (rGO) enhance its electrical conductivity. Atomic structural information thermally annealed (GO) provides an understanding how heteroatomic doping could affect electronic property rGO. Herein, spectroscopic and microscopic variations during thermal graphitization from 573 to 1,373 K are reported in two different rGO sheets, prepared by annealing GO (rGO(therm)) post-thermal chemically nitrogen-doped...
Thin-film transistors (TFTs) have received great attention for their use in lightweight, large area, and wearable devices. However, low crystalline materials inhomogeneous film formation limit the realization of high-quality electrical properties channels commercial TFTs, especially flexible electronics. Here, we report a field-effect TFT fabricated via cross-linking edge-1T basal-2H MoS2 sheets that are prepared by edge functional exfoliation bulk with soft organic reagents. For...