A5009575900- Quantum Dots Synthesis And Properties
- Nonlinear Optical Materials Research
- Perovskite Materials and Applications
- Organic Electronics and Photovoltaics
- Chalcogenide Semiconductor Thin Films
- Nonlinear Optical Materials Studies
- Photorefractive and Nonlinear Optics
- Photochromic and Fluorescence Chemistry
- Synthesis and properties of polymers
- Conducting polymers and applications
- Luminescence and Fluorescent Materials
- Liquid Crystal Research Advancements
- 2D Materials and Applications
- Organic Light-Emitting Diodes Research
- Nanofabrication and Lithography Techniques
- Photonic Crystals and Applications
- bioluminescence and chemiluminescence research
- Nanoplatforms for cancer theranostics
- Photonic and Optical Devices
- Thin-Film Transistor Technologies
- Photoreceptor and optogenetics research
- Molecular Sensors and Ion Detection
- MXene and MAX Phase Materials
- Surface Roughness and Optical Measurements
- Ga2O3 and related materials
Hannam University
2009-2022
Daejeon University
2018
Government of the Republic of Korea
2018
University at Buffalo, State University of New York
2000-2008
Novel two-photon absorption (TPA) chromophores are synthesized; they have dithienothiophene (DTT) as a π-center which is attached by electron donor (D) or acceptor (A) at each end through π-conjugation. Their TPA cross section, measured using nanosecond- well femtosecond-pulsed laser, exhibits one of the largest values known so far. This attributable mainly to unique electronic properties DTT.
We demonstrate a relative improvement in power conversion efficiency of polymer nanocomposite photovoltaic cells consisting poly(3-hexylthiophene) (P3HT) functionalized CdSe nanocrystals. Thermal deprotection processing the tert-buthoxycarbonyl moiety carbamate ligand surrounding surface nanocrystal significantly shortened length between nanocrystals and matrix. The resulting device performance was investigated as function composition ratio P3HT/CdSe heating temperature. This simple...
This paper reports synthesis and semiempirical modeling of 1,4-bis(cyanostyryl)benzene (CSB)-based quadrupolar isomeric molecules (α- β-CSB-TPs), designed to produce enhancement in fluorescence quantum yield two-photon absorption cross-sections for the nanoaggregate form. Fluorescence together with high optical properties isomers have been fine-tuned by moving cyano group from α β position, which results longer absorption-fluorescence wavelengths, higher one- absorptivities β-CSB-TP. In...
We report an approach to produce predefined patterns of quantum dots and multipod nanocrystals using optical lithography for direct writing films optoelectronic electronic devices. To obtain photopatternability, the nanostructures (for example, CdSe, CdTe, PbSe nanocrystals) were functionalized by incorporation functional ligand t-butoxycarbonyl (t-BOC) which has acid-labile moiety. This change in surface chemistry results ability photopattern semiconductor where desired a number device...
Silicon solar cells mainly absorb visible light, although the sun emits ultraviolet (UV), visible, and infrared light. Because surface reflectance of a textured with SiNX film on silicon cell in UV wavelength region (250–450 nm) is higher than ∼27%, solar-cells cannot effectively convert light into photo-voltaic power. We implemented concept energy-down-shift using CdSe/ZnS core/shell quantum-dots (QDs) p-type to more QDs demonstrated clear evidence energy-down-shift, which absorbed emitted...
Perovskite CsPbX3 (X = Br, Cl, and I) nanostructures have been intensively studied as they are luminescent, photovoltaic, photosensitizing active materials. Two-dimensional (2D) transition-metal dichalcogenides (TMDCs) with MX2 (M Mo, W; X S, Se, Te, etc.) structures used in flexible optoelectronic devices. In this study, perovskite green-light-emitting CsPbBr2I1 quantum dots (QDs) blue-light-emitting CsPb(Cl/Br)3-QDs utilized to enhance the photoresponsive characteristics of 2D MSe2 Mo...
We correlate appearance of nano black spots (NBSs), optical stability and Goldschmidt tolerance factor (<italic>t</italic>) in mixed halide perovskite QDs.
Three functionalized second-order nonlinear optical polyimides were synthesized by the step growth polymerization reaction between a chromophore-containing dianhydride and three different diamine compounds. This alternate approach (i.e., incorporating chromophore into monomer) may avoid troublesome syntheses of can provide easy preparation with various chromophores. The number-average molecular weights (Mn) final polymers determined GPC ranged 10 000 16 800 (Mw/Mn = 1.59−2.28). No melting...
Hybrid nanosystems comprising functionalized CdSe/ZnS core–shell quantum dots (QDs) on the surface of light-emitting poly(3-hexylthiophene) (P3HT), metallic copper (Cu), and insulating polystyrene (PS) nanowires (NWs) are fabricated. Using high-resolution scanning transmission electron microscopy, we observe that QDs attached to NWs. The nanoscale photoluminescence (PL) characteristics hybrid QD/P3HT, QD/Cu, QD/PS single NWs investigated using laser confocal microscopy (LCM) with high...
Three types of different cross-linked polyurethane were prepared by the reaction poly[(phenylisocyanate)-co-formaldehyde] with three hydroxy-functionalized nonlinear optical chromophores. For poled and cured polymers χ(2) values between 16.8 37.4 pm/V, measured at a wavelength 1.064 μm. Thermal stability studies performed on sample having bonding sites vertical–parallel structure chromophore liquid polymer matrix indicated, second-harmonic-generation activity, minimum decay value owing to...
We report the synthesis and biological studies of a fluorescence dye with an oligoethylene glycol substituted (OEG) perylene centered N,N’-(2,6-diisopropylphenyl)-1-[oligo(ethylene glycol)methyl ether]-1,6,7,12-trichloroperylene-3,4:9,10-tetracarboxdiimide (PDI-OEG). The activity is juxtaposed precursor molecule without OEG substitution. substitution contributes to increased biocompatibility PDI-OEG. Cell viability lead survival more than 80% PDI-OEG cultured cells endorsing its...
Department of Polymer Sceince and Engineering, Hannam University, Daejeon 306-791, KoreaReceived May 10, 2002Keywords :Photoactive polyester, Cinnamoyl group, UV irradiation, Photo-crosslinking, Step-reaction poly-merization.Photosensitive polymers with photo-crosslinkable groupshave gained a considerable interest in recent years owing toa wide variety applications the field potoresists,photocurable coatings, microlithography, nonlinear optics,energy exchange materials, photosensitizers, etc.
Biophotonics can be defined as the interplay of light and biological matter. The percolation new optical technology into realm biology has literally shed inner workings systems. This revealed applications for optics in biology. In a parallel trend, biomolecules have been investigated their applications. Materials are playing central role development biophotonics. New materials, fabrication methods, structures enabling biosensors, contrast agents, imaging strategies, assay methods. Similarly,...