Yoonsoo Kim

As a new class of materials, implantable flexible electrical conductors have recently been developed and applied to bioelectronics. An ideal electrical conductor requires high conductivity, tissue-like mechanical properties, low toxicity, reliable adhesion to biological tissues, and the ability to maintain its shape in wet physiological environments. Despite significant advances, electrical conductors that satisfy all these requirements are insufficient. Herein, a facile method for manufacturing

As novel functional materials, we developed self-oscillating polymeric materials composed of synthetic polymers coupled with an oscillating chemical reaction, the so-called Belousov–Zhabotinsky (BZ) reaction.

Monodispersed ZnO nanoparticles are easily prepared by the thermolysis of EtZnO(i)Pr as a single molecular precursor and TOPO without any extra solvent as well as any oxygen source.

The phenomenon of low initial growth rates in atomic layer deposition (ALD) of various oxides on HF-treated (thus H-terminated) Si(001) substrates, which is termed the incubation effect or incubation period, can be effectively avoided by use of OH-terminated Si(001) substrates. Two ways of preparing OH-terminated Si(001) were devised in this work: one from atomically clean Si(001) and the other from H-terminated Si(001). The effect of reducing the incubation period was confirmed in the ALD proce

Abstract High‐capacity anode materials are promising candidates for increasing the energy density of lithium (Li)‐ion batteries due to their high theoretical capacities. However, a rapid capacity fading due to the huge volume changes during charge‐discharge cycles limits practical applications. Herein, a layering‐charged polymeric binder is introduced that can effectively integrate high‐capacity anodes using a strong yet reversible Coulomb interaction and enriched hydrogen bonding. The charged p

Abstract Thin films of gallium oxide (Ga 2 O 3 ) are prepared by using a new gallium precursor, dimethylgallium isopropoxide (DMGIP), employing both atomic layer deposition (ALD) and metal‐organic (MO)CVD. The gallium precursor DMGIP, a gallium analogue of dimethylaluminum isopropoxide (DMAIP) that has been successfully used for MOCVD and ALD of aluminum oxide, is likewise a non‐pyrophoric liquid at room temperature with a reasonably high vapor pressure. Using water as the oxygen source, DMGIP s

Abstract Aqueous zinc metal batteries (AZMBs) are emerging energy storage systems that are poised to replace conventional lithium‐ion batteries owing to their intrinsic safety, facile manufacturing process, economic benefits, and superior ionic conductivity. However, the issues of inferior anode reversibility and dendritic plating during operation remain challenging for the practical use of AZMBs. Herein, a gel electrolyte based on zwitterionic poly(sulfobetaine methacrylate) (poly(SBMA)) dissol

The adsorption of vinylacetic acid (VAA) on the Si(001)2×1 surface has been investigated using low-energy electron diffraction, X-ray photoelectron spectroscopy, and synchrotron radiation photoemission spectroscopy. VAA adsorbs on the Si(001)2×1 surface at room temperature, not through the reaction of the vinyl group (CH 2 CH−) but through the dissociative adsorption of RCOOH (R = CH 2 CHCH 2 ) into RCOO(ad) as a unidentate adsorbate and H(ad) without breaking the Si dimers. Curve-fitting of the

MgO films have been grown on Si(111) and Si(100) substrates at 400−800 °C by using methylmagnesium tert -butoxide as a single precursor under high-vacuum conditions (5 × 10 - 6 Torr). The methylmagnesium tert -butoxide precursor was synthesized and characterized by spectroscopic methods and single-crystal X-ray diffraction analysis. The chemical composition, crystalline structure, and morphology of the deposited films were investigated by X-ray photoelectron spectroscopy, X-ray diffraction, X-ra

Thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) hydrogels have been attracting attention in a variety of functional materials, such as biomaterials, because they exhibit a volume phase transition phenomenon near physiological temperatures. However, the slow kinetics and small volume shrinkage of bulk PNIPAAm hydrogels upon heating greatly limit their practical application. Here, we report PNIPAAm hydrogels with phase-separated structures that exhibited ultrafast shrinking upon heating. Th