A5067447794- Photonic Crystals and Applications
- TiO2 Photocatalysis and Solar Cells
- Advanced Photocatalysis Techniques
- Advancements in Battery Materials
- Quantum Dots Synthesis And Properties
- Supercapacitor Materials and Fabrication
- Advanced Battery Materials and Technologies
- Photonic and Optical Devices
- Nanofabrication and Lithography Techniques
- Conducting polymers and applications
- Advanced Battery Technologies Research
- Advanced battery technologies research
- Pickering emulsions and particle stabilization
- Copper-based nanomaterials and applications
- Electrocatalysts for Energy Conversion
- Perovskite Materials and Applications
- Optical Coatings and Gratings
- Microfluidic and Bio-sensing Technologies
- CO2 Reduction Techniques and Catalysts
- Mesoporous Materials and Catalysis
- Transition Metal Oxide Nanomaterials
- Catalytic Processes in Materials Science
- Electrowetting and Microfluidic Technologies
- Photochemistry and Electron Transfer Studies
- Nonlinear Optical Materials Studies
Korea University
2023-2025
Sogang University
2014-2023
Government of the Republic of Korea
2015-2021
Seoul Institute
2020-2021
Samsung (South Korea)
2007-2020
Yeungnam University College
2016
Yeungnam University
2016
Korea Advanced Institute of Science and Technology
2001-2012
Sungkyunkwan University
2009-2010
Samsung Medical Center
2010
A carbon host capable of effective and uniform sulfur loading is the key for lithium–sulfur batteries (LSBs). Despite application porous materials various morphologies, hosts uniformly impregnating highly active still challenging. To address this issue, we demonstrate a hierarchical pore-structured CNT particle containing spherical macropores several hundred nanometers. The macropore particles (M-CNTPs) are prepared by drying aerosol droplets in which CNTs polymer dispersed. greatly improves...
Highly monodispersed nitrogen-doped carbon nanospheres are prepared by the pyrolytic carbonization of emulsion-polymerized polystyrene-based colloidal spheres in presence a nitrogen-enriched molecule, melamine (1,3,5-triazine-2,4,6-triamine). The successfully tested for use as electrode materials supercapacitors. nitrogen content incorporated into sphere is controlled changing weight ratio to polymer spheres. doping concentration proportional mixing ratio. produces relatively abundant...
Abstract The fabrication of true three‐dimensional (3D) microstructures both rapidly and economically over a large area with negligible defects is attractive for wide range applications. In particular, multi‐beam interference lithography one the promising techniques that can mass‐produce polymeric 3D photonic crystals defect‐free area. This review discusses relationship between beam geometry symmetry patterns, lithographic process, various types photoresist systems, including thick films...
Superhydrophobic nanofiber films were created from electrospun nanofibers with undulated surfaces at multiple scales in micrometers and nanometers. The produced out of aqueous solutions which contained water-soluble polymers different colloids: monodisperse silica or polystyrene microspheres for larger particles nanoparticles smaller particles. Various types fibrous depending on the properties dispersing medium, effects additives, compositions bidisperse colloids. When used as sacrificial...
We introduce MnO2 nanoflake/carbon nanotube (CNT) core–shell particles for high-performance supercapacitors. The CNT prepared by drying the CNT-dispersed aerosol produce a tightly intertwined assembly internal capillary force, and subsequent growth of on surface produces high area nanoflake shell. control amount decoration obtain specific capacitance 370 F/g at current density 0.5 A/g upon their supercapacitor electrode application. This is 14 times higher than that bare 3 particles. An...
Complete encapsulation of high-content sulfur in porous carbon is crucial for high performance Li-S batteries. To this end, unlike conventional approaches to control the pore hosts, we demonstrate controlling interfacial energy solution process penetrating sulfur-dissolved solution. We unveil, experimentally and theoretically, that with surface key driving complete sulfur. In infiltration solutions N-methyl-2-pyrrolidone, achieve sulfur, even up 85 wt %. The fully encapsulated cathode...
We report the photocatalytic conversion of CO2 to CH4 using CuPt alloy nanoclusters anchored on TiO2. As size decreases, activity improves significantly. Small strongly bind intermediates and have a stronger interaction with TiO2 support, which also contributes an increased generation rate. The alloying effects prove be key efficient reduction, highlighting strategic platform for design photocatalysts conversion.
Abstract Due to the greenhouse effect, enormous efforts are done for carbon dioxide reduction. By contrast, more attention should be paid methane oxidation and conversion, which can help effective utilization of without emission. However, conversion under ambient conditions remains a challenge. Here, this study designs Co 3 O 4 /ZrO 2 nanocomposite electrochemical gas using carbonate electrolyte at room temperature. activated highly efficient mild electric energy with as an oxidant, is...
Fe–N–C single atom catalysts (SACs) utilize active oxygen from the evolution reaction for efficient methane-to-ethanol conversion, achieving an ethanol production rate of 11 480.6 μmol g cat −1 h in flow cell reactions.
Photonic balls have been fabricated (see Figure) by field‐enhanced electrospray of an aqueous colloidal suspension. The polystyrene (PS) beads inside the suspension droplets self‐organize into opaline while solvent evaporates. are used as templates for inverse photonic balls, and both types exhibit varying reflection colors depending on diameter reflective index contrast.
This letter presents a biomimetic humidity sensor inspired by the humidity-dependent color change observed in cuticle of Hercules beetle. A thin-film-type with nanoporous structures (three-dimensional photonic crystals) mimicking spongy multilayer beetles was designed and fabricated using colloidal templating method hydrophilic surface treatment. The visible changes from blue-green to red as environmental increases. wavelength reflected light that is predicted Bragg’s equation considering...
Well-defined three dimensional photonic crystals (PCs) of hydrogels are fabricated by prism holographic lithography over large areas. The hydrogel PCs, swollen in the humidity air, show a tunable optical stop-band response to temperature. thermoresponsive behavior is caused viscoelastic deformation upon temperature change, which investigated capturing structure with silica.
For the first time, double-deck WO3/BiVO4 inverse opal photoanodes (DDIO-WO3/BiVO4) were prepared by swelling–shrinking mediated polystyrene template synthetic routes, and use of in photoelectrochemical cells under simulated solar light was investigated. The represented compact interface between WO3 BiVO4, inheriting periodically ordered macroporous nanostructure. More significantly, DDIO-WO3/BiVO4 from optimized fabrication condition demonstrated a photocurrent that ∼40 times higher than...
We examine the effects of chlorine-passivation Cd surface atoms on photocatalytic H2O reduction by CdSe NCs. Transient absorption spectroscopy reveals that Cl passivation removes electron trap states in NCs, which is also reflected an increase photoluminescence quantum yield, e.g., from 9 to 22% after treatment. Size-tunable energy NCs enable systematic investigation defects and their effect hydrogen generation rate. It turns out that, depending band-edge levels, may enhance or inhibit...
We for the first time demonstrated carbon-deposited TiO2 inverse opal (C-TiO2 IO) structures as highly efficient visible photocatalysts. The carbon deposition proceeded via high-temperature pyrolysis of phloroglucinol/formaldehyde resol, which had been coated onto IO structures. Carbon formed a layer and doped interface, synergistically enhanced visible-light absorption. directly measured photocatalytic activity by constructing solar cells comprising C-TiO2 electrode. Photocatalytic...
Abstract Mechanical metamaterials that are engineered with sub-unit structures present unusual mechanical properties depending on the loading direction. Although they show promise, their practical utility has so far been somewhat limited because, to best of our knowledge, no study about potential made from sophisticatedly tailored made. Here, we a metamaterial whose can be systematically designed without changing its chemical composition or weight. We triply periodic bicontinuous detailed...
Electrochemical CH4 oxidation is attractive as a strategy capable of conversion with high selectivity, but improving productivity remains challenge. We demonstrate that CuO/CeO2 can serve catalyst for the room-temperature to CH3OH in presence CO32–. At an optimized ratio (Cu:Ce = 6:4), we achieve highest production rate 752.9 μmol/gcat/h (6 h reaction) at ambient pressure; among oxygenates, selectivity 79% obtained. In experiment using isotopes, confirm activated by active oxygen on surface...