A5100443311- Material Dynamics and Properties
- Advanced NMR Techniques and Applications
- Solid-state spectroscopy and crystallography
- X-ray Diffraction in Crystallography
- Luminescence and Fluorescent Materials
- Crystallization and Solubility Studies
- Atomic and Subatomic Physics Research
- Force Microscopy Techniques and Applications
- Phase Equilibria and Thermodynamics
- Microfluidic and Capillary Electrophoresis Applications
- Photochemistry and Electron Transfer Studies
- Advanced Fluorescence Microscopy Techniques
- Quantum Electrodynamics and Casimir Effect
- Porphyrin and Phthalocyanine Chemistry
- Photochromic and Fluorescence Chemistry
- Advanced Nanomaterials in Catalysis
- Various Chemistry Research Topics
- Perovskite Materials and Applications
- Electrocatalysts for Energy Conversion
- Spectroscopy and Quantum Chemical Studies
- Molecular spectroscopy and chirality
- Quantum Dots Synthesis And Properties
- Organic and Molecular Conductors Research
- Acoustic Wave Resonator Technologies
- Mechanical and Optical Resonators
Sungkyunkwan University
2018-2024
University of Arizona
2018-2023
Inha University
2018
University of Rochester
2010
University of Cincinnati
2005-2007
University of California, Riverside
2005-2006
The dyads 3, 4, and 6, combining the Bodipy chromophore with a Pt(bpy)(bdt) (bpy = 2,2'-bipyridine, bdt 1,2-benzenedithiolate, 3 6) or Pt(bpy)(mnt) (mnt maleonitriledithiolate, 4) moiety, have been synthesized studied by UV-vis steady-state absorption, transient emission spectroscopies cyclic voltammetry. Comparison of absorption spectra voltammograms 6 those their model compounds 1a, 2, 5, 7 shows that spectroscopic electrochemical properties are essentially sum constituent chromophores,...
Nanoparticles of a novel organic zwitterionic Meisenheimer complex, N',N' ',N' ''-tri(isopropyl)-4-oxo-6-(isopropyliminio)-2-s-(2H)triazinespiro-1'-2',4',6'-trinitrocyclohexadienylide, were synthesized by reprecipitation in water under different conditions. While alone resulted suspension amorphous particles that fell out solution within hours, sonication for periods time the formation crystalline stable over course weeks. The disk-shaped had an average diameter 140 nm and thickness 70 nm....
Abstract Rotational-translational decoupling, in which translational motion is apparently enhanced over rotational violation of Stokes-Einstein (SE) and Debye-Stokes-Einstein (DSE) predictions, has been observed materials near their glass transition temperatures (T g ). This posited to result from ensemble averaging the context dynamic heterogeneity. In this work, single molecule experiments are performed parallel on a fluorescent probe high molecular weight polystyrene its T . Ensemble...
Polymer networks generally consist of an ensemble single chains. However, understanding how chain conformation affects the structure and properties polymer remains a challenge for optimizing their functionality. Here, we present fabrication comparative study network composed collapsed self-entangled chains (intrachain entangled network) standard in which random-coil are with each other (interchain network). For poly(methyl methacrylate) thin films these networks, coupled solvent vapor...
How tethered probes report dynamics of host polymers near the glass transition was investigated by changing length flexible linkers and number tethering points via imaging rotational fluorescence correlation microscopy compared with free different sizes. The results show that did not alter temperature-dependence polymer shape decay reported probe; however, rotation slowed down up to ≈1 decade when both ends probe were restricted short alkyl chain linkers. Upon comparison bigger probe,...
The approach of utilizing polymer-tethered fluorescent molecules in probing segmental dynamics polymers near the glass transition was validated by examination rotational probes that were randomly dispersed same polymer hosts as tethered polymers. Poly(alkyl methacrylate)- and polystyrene-tethered probes, located either at end or middle a chain, with flexible dodecyl hexyl alkyl chains atom transfer radical polymerization post-polymerization modification, respectively. Different polymeric...
Al2O3 filters (200 nm) are used as templates to form polymer nanotubes containing an energy donor (perylene). The perylene is isolated from chemical interactions but can undergo electronic transfer acceptor molecules in aqueous solutions passing through the membrane. This analyzed quantitatively terms of both radiative and nonradiative (Forster transfer) mechanisms provides a way for chemically inert filter sense presence analyte filtrate.
The segmental dynamics of polymers is known to be closely related the glass transition where single most important parameter in its application. In this study, we designed an efficient and reliable experimental method study ensemble by probing rotation fluorescent molecules polymer matrix using a home-built microscope setup. rotational was analyzed fluorescence correlation that extracts information through orthogonally polarized images. From intensities, autocorrelation functions (ACFs) were...
This study investigated the segmental dynamics of polymers near polymer–polymer interfaces by probing rotation polymer-tethered fluorescent molecules using imaging rotational fluorescence correlation microscopy. Multilayered films were utilized to provide spatial selectivity relative different interfaces. In experimental setup, for overlayer polymer, polystyrene (PS) was employed and a 15 nm-thick probe-containing layer placed ≈25 nm apart from underlayer with glass transition temperatures...
Piezoelectric copolymer, PVDF-TrFE, diaphragm arrays with integrated microfluidic chip for high performance protein immunosensors were developed and characterized in this work. Mold-transfer hot-embossing techniques provide a throughput repeatable way to fabricate piezoelectric polymer diaphragms PVDF-TrFE's hydrophobic surface acts as natural bioreceptor capture proteins of interest. In addition, devices enhance reaction efficiency reduce the assay time.
The rotational dynamics of fluorescent probes different sizes in glass-forming materials were examined to correlate the time distribution and length scale dynamic heterogeneity (ξhet). As size probe increased, temperature dependence rotation correlation (τc) shifted longer times, from this shift, associated with glass transition (ξα) was estimated through Debye-Stokes-Einstein (DSE) relationship (ξsDFT) quantum mechanical calculations. ξα values roughly matched ξhet obtained calorimetric...
Multi-Layered PtAu Nanoframes In article number 2206377, Insub Jung, Sungho Park, and co-workers present the rationale design of multi-layered nanoframes via multiple synthetic pathways for plasmon-enhanced electrocatalytic activity. Plasmonic hot spots formed between inner outer frames promote light-induced enhancement toward methanol oxidation reaction. Notably, authors demonstrate correlation with efficiency by precisely tuning distance nanogaps.