Jungki Ryu 교수

Abstract Bone tissue is a complex biocomposite material with a variety of organic (e.g., proteins, cells) and inorganic (e.g., hydroxyapatite crystals) components hierarchically organized with nano/microscale precision. Based on the understanding of such hierarchical organization of bone tissue and its unique mechanical properties, efforts are being made to mimic these organic–inorganic hybrid biocomposites. A key factor for the successful designing of complex, hybrid biomaterials is the facilit

Treatment of amorphous diphenylalanine thin film at high temperatures as 150 °C with aniline vapor under anhydrous condition results in the formation of vertically well-aligned nanowires. By combining the high-temperature aniline vapor aging method with a simple soft-lithographic technique, we could fabricate a micro-scale pattern of vertically-grown peptide nanowires. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2089/2008/adma20080036

We report the synthesis of novel diphenylalanine/cobalt(II,III) oxide (Co(3)O(4)) composite nanowires by peptide self-assembly. Peptide nanowires were prepared by treating amorphous diphenylalanine film with aniline vapor at an elevated temperature. They were hybridized with Co(3)O(4) nanocrystals through the reduction of cobalt ions in an aqueous solution using sodium borohydride (NaBH(4)) without any complex processes such as heat treatment. The formation of peptide/Co(3)O(4) composite nanowir

Chiral compounds are successfully photosynthesized by coupling redox biocatalysis with the photoregeneration of nicotinamide cofactors on quantum-dot-sensitized TiO2 nanotubes under visible light irradiation. Nanotubular morphology and hybridization of TiO2 with CdS enables highly efficient photoregeneration of cofactors by ensuring better diffusion of reaction species and rapid charge separation. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such

Peptide Self-Assembly for Lithium Ion Batteries: Nanostructures of transition metal phosphates were fabricated through biomimetic mineralization of self-assembled peptide hydrogel nanofibers. FePO4-mineralized peptide nanofibers were readily converted to carbon-coated FePO4 nanotubes after heat treatment and exhibited a high and reversible charge/discharge capacity as Lithium ion battery cathodes.

Photoluminescent peptide nanotubes are synthesized in an in situ incorporation of lanthanide complexes into peptide nanotubes through a self-assembly process. We found that peptide nanotubes and photosensitizer molecules exhibited a high synergistic effect on the enhancement of lanthanide photoluminescence through a cascaded energy-transfer mechanism. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edite

The efficient removal of gas bubbles in (photo)electrochemical gas evolution reactions is an important but underexplored issue. Conventionally, researchers have attempted to impart bubble-repellent properties (so-called superaerophobicity) to electrodes by controlling their microstructures. However, conventional approaches have limitations, as they are material specific, difficult to scale up, possibly detrimental to the electrodes' catalytic activity and stability, and incompatible with photoel

Understanding the self-assembly of peptides into ordered nanostructures is recently getting much attention since it can provide an alternative route for fabricating novel bio-inspired materials. In order to realize the potential of the peptide-based nanofabrication technology, however, more information is needed regarding the integrity or stability of peptide nanostructures under the process conditions encountered in their applications. In this study, we investigated the stability of self-assemb

Abstract Removal of gas bubbles from the electrode surface is practically important to maintain the activity of electrochemical gas evolution reactions. Conventionally, most studies have focused on the development of electrocatalysts and paid less attention to the bubble removal issues. Recently, it has been reported that attached gas bubbles can be readily eliminated by imparting extremely gas‐repellent properties (so‐called superaerophobicity) to electrodes via controlling their nano/microstru

An efficient and stable heterojunction photoanode for solar water oxidation was fabricated by hybridization of WO₃ and conducting polymers (CPs). Organic/inorganic hybrid photoanodes were readily prepared by the electropolymerization of various CPs and the codeposition of tetraruthenium polyoxometalate (Ru₄POM) water-oxidation catalysts (WOCs) on the surface of WO₃. The deposition of CPs, especially polypyrrole (PPy) doped with Ru₄POM (PPy:Ru<sub>4</su

Breaking the mold: Self-assembled peptide nanowires were used as a template for the synthesis of hollow polyaniline (PANI) nanotubes (see scanning electron microscopy images). The thickness and the morphology of the PANI nanostructures could be controlled readily either by varying the reaction time or by applying multiple PANI coatings.

The physical and photochemical properties of covalent organic frameworks (COFs) can be tuned by their structural features such as the chemical composition and conjugation of building units. The combination of building units with different intrinsic properties can also influence their intrinsic electronic, adsorption, and optical properties. For the study on the symmetrical feature of COF and its physical/photochemical properties, we prepared benzothiazole-based COFs (TTzTp and BTzTp) with two di

Inspired by nature's strategy for creating organic/inorganic hybrid composite materials, we developed a simple but powerful method to synthesize bone-like peptide/hydroxyapatite nanocomposites using a mussel-mimetic adhesive, polydopamine. We found that polydopamine was uniformly coated in a graphite-like layered structure on the surface of self-assembled diphenylalanine (Phe-Phe, FF) nanowires and enabled the epitaxial growth of c-axis-oriented hydroxyapatite nanocrystals along the nanowires, w

We analyzed the aggregation of Alzheimer's beta-amyloid (1-42) (Abeta42) peptides from fresh monomers to fully grown fibrils by using in situ surface plasmon resonance (SPR) spectrometry and ex situ atomic force microscopy (AFM). To immobilize Abeta42 peptide on an SPR chip surface, different carboxy-terminated surfaces were investigated: (1) self-assembled monolayer of 11-mercaptoundecanoic acid and (2) carboxylated dextran-modified surface. It was found that the carboxylated dextran surface wa

An efficient and stable bias-free photoelectrochemical cell was readily fabricated using only simple solution processes.