Dong‐Hwan Kim

Based on the localized surface plasmon resonance (LSPR) of metallic nanoparticles, plasmonic nanosensors have emerged as a powerful tool for biosensing applications. Many detection schemes have been developed and the field is rapidly growing to incorporate new methodologies and applications. Amidst all the ongoing research efforts, one common factor remains a key driving force: continued improvement of high-sensitivity detection. Although there are many excellent reviews available that describe

Abstract The use of biologically active dopants in conductive polymers allows the polymer to be tailored for specific applications. The incorporation of nerve growth factor (NGF) as a co‐dopant in the electrochemical deposition of conductive polymers is evaluated for its ability to elicit specific biological interactions with neurons. The electrochemical properties of the NGF‐modified conducting polymers are studied by impedance spectroscopy and cyclic voltammetry. Impedance measurements at the

The conducting polymer polypyrrole (PPy) was electrochemically grown on hydrogel scaffolds deposited on the surface of microfabricated neural prosthetic devices. It is shown that the pyrrole monomer can be grown vertically through the hydrogel layer up to the surface without affecting the adjacent sites on the probes. The electrochemical properties of the conducting polymer-modified hydrogels were studied by impedance spectroscopy and cyclic voltammetry. It is also found that the conducting poly

We report a novel composite material of hierarchically structured Mn₃O₄ grown on three-dimensional graphene foam (3DGF). This hierarchical Mn₃O₄/3DGF composite was fabricated as a flexible and freestanding biosensor for nonenzymatic determination of glucose and H₂O₂, significant analytes in health care and food industry. The Mn₃O₄/3DGF-based biosensor achieved high sensitivity, large linear range and low dete

A novel nanoplatelet-like structure of the composites of polypyrrole (PPy) and graphene (GR) is facilely synthesized by an electrochemical method and is further employed as a supercapacitor. The nanocomposite of PPy/GR shows a porous structure with a specific surface area of as high as 136.5 m2 g−1. As a result, the composite material exhibits a high specific capacitance of 285 F g−1 at a discharge rate of 0.5 A g−1, and excellent cycling stability. Specifically, over 90% of its initial capacita

A novel method is developed to fabricate the polypyrrole (PPy) and graphene thin films on electrodes by electrochemical polymerization of pyrrole with graphene oxide (GO) as a dopant, followed by electrochemical reduction of GO in the composite film. The composite of PPy and electrochemically reduced graphene oxide (eRGO)-modified electrode is highly sensitive and selective toward the detection of dopamine (DA) in the presence of high concentrations of ascorbic acid (AA) and uric acid (UA). The

Abstract Human sweat contains vast physiological information, which has been a promising resource for on‐body and real‐time health monitoring. Wearable sweat sensors have recently attracted an ever‐increasing interest due to their promising capabilities for continuously tracking changes in health status. However, the commercialization of sweat sensors is seriously hindered by drawbacks of materials including high manufacturing and consumables costs, complex integration technology, as well as lim

We propose a novel origin of magnetic anisotropy to explain the unusual magnetic behaviors of layered ferromagnetic Cr compounds (3d^{3}) wherein the anisotropy field varies from ≲0.01 to ∼3 T on changing the ligand atom in a common hexagonal structure. The effect of the ligand p orbital spin-orbit (LS) coupling on the magnetic anisotropy is explored by using four-site full multiplet cluster model calculations for energies involving the superexchange interaction at different spin axes. Our calcu

We report the synthesis of uniform triangular gold nanoplates by a modified seeded growth method. The concentration of cetyltrimethylammonium bromide (CTAB) in the growth solution and the time interval between multiple steps of growth were important factors which determined the formation of uniform triangular Au nanoplates. In addition, by further isotropic overgrowth, the thickness of triangular Au nanoplates can be finely tuned within a wide range of 10-80 nm, which at present remains a challe

Orientation sensors require the monitoring of polarization-dependent surface plasmons of single nanoparticles. Herein, we present both the longitudinal and transverse surface plasmonic resonance from a single gold nanorod (AuNR) using conventional dark-field microscopy. The relative peak intensities of the transverse and longitudinal surface plasmons of a single AuNR can be successfully tuned by polarized excitation, which is an important step towards the use of transverse plasmon resonance of s

Transparent electrodes based on conventional indium-tin oxide (ITO) can hardly meet the requirements of future generations of stretchable electronic devices, including artificial skins, stretchable displays, sensors, and actuators, because they cannot retain high conductivity under substantial stretching and bending deformation. Here we suggest a new approach for fabricating highly stretchable and transparent electrodes with good stability in environments where they would be stretched repeatedly