• Research Paper

    Development of Zinc-Doped Titanium Dioxide Coatings with Enhanced Biocompatibility for Biomedical Application
    Minseo Yu, Yo Han Song, Mi-Kyung Han
    The surface of titanium (Ti) dental implants was modified by applying a zinc (Zn)-doped titanium dioxide (TiO2) coating. Initially, the … + READ MORE
    The surface of titanium (Ti) dental implants was modified by applying a zinc (Zn)-doped titanium dioxide (TiO2) coating. Initially, the Ti surfaces were etched with NaOH, followed by a hydrolysis co-condensation using tetrabutyl titanate (TBT, Ti(OC4H9)4) and zinc nitrate hexahydrate (Zn(NO3)2 ‧ 6H2O), with ammonia water (NH3 ‧ H2O) acting as a hydroxide anion source. The morphology and chemical composition of the Zn-doped TiO2-coated Ti plates were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and scanning electron microscopy (SEM). Synthesis temperatures were carefully adjusted to produce anatase Zn-doped TiO2 nanoparticles with a bipyramidal structure and approximate sizes of 100 nm. Wettability tests and cell viability assays demonstrated the biomedical potential of these modified surfaces, which showed high biocompatibility with a survival rate of over 95 % (p < 0.05) and improved wettability. Corrosion resistance tests using potentiodynamic polarization reveal that Zn-TiO2-treated samples with an anatase crystal structure exhibited a lower corrosion current density and more noble corrosion potential compared to samples coated with a rutile structure. This method offers a scalable approach that could be adapted by the biomaterial industry to improve the functionality and longevity of various biomedical implants. - COLLAPSE
    PDFXMLCitation
    ReferencesInformation
    27 August 2024

  • Research Paper

    Hydrated Vanadium Pentoxide/Graphene Oxide Nanobelts for Enhanced Electrochemical Performance
    Hyegyeong Hwang, Jinsung Kwak
    Transition metal oxide-based materials have mainly been studied as electrodes for energy storage devices designed to meet essential energy demands. Among transition … + READ MORE
    Transition metal oxide-based materials have mainly been studied as electrodes for energy storage devices designed to meet essential energy demands. Among transition metal oxide-based materials, hydrated vanadium pentoxide (V2O5 ‧ nH2O), a vanadium oxide material, has demonstrated great electrochemical performance in the electrodes of energy storage devices. Graphene oxide (GO), a carbon-based material with high surface area and high electrical conductivity, has been added to V2O5 ‧ nH2O to compensate for its low electrical conductivity and structural instability. Here, V2O5 ‧ nH2O/GO nanobelts are manufactured with water without adding acid to ensure that the GO is uniformly dispersed, using a microwave-assisted hydrothermal synthesis. The resulting V2O5 ‧ nH2O/GO nanobelts exhibited a high specific capacitance of 206 F/g and more stable cycling performance than V2O5 ‧ nH2O without GO. The drying conditions of the carbon paper electrodes also resulted in more stable cycling performance when conducted at high vacuum and high temperature, compared with low vacuum and room temperature conditions. The improvement in electrochemical performance due to the addition of GO and the drying conditions of carbon paper electrodes indicate their great potential value as electrodes in energy storage devices. - COLLAPSE
    PDFXMLCitation
    ReferencesInformation
    27 August 2024

  • Research Paper

    Silicon-Organic Hybrid Solar Cell Using Ag Nanowire/PEDOT:PSS Layer

    은 나노와이어/PEDOT:PSS를 이용한 실리콘-유기물 하이브리드 태양전지

    Kyudong Kim, Sungjin Jo

    김규동, 조성진

    Among various organic materials suitable for silicon-based inorganic-organic hybrid solar cells, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has been extensively studied due to its high … + READ MORE
    Among various organic materials suitable for silicon-based inorganic-organic hybrid solar cells, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has been extensively studied due to its high optical transmittance, high work function, and low bandgap characteristics. The electro-optical properties of PEDOT:PSS have a significant impact on the power conversion efficiency of silicon-organic hybrid solar cells. To enhance the photovoltaic properties of the silicon-organic hybrid solar cells, we developed a method to improve the properties of the PEDOT:PSS film using Ag nanowires (NW) instead of conventional solvent addition methods. The influence of the Ag NW on the electro-optical property of the PEDOT:PSS film and the photovoltaic performance of the silicon-organic hybrid solar cells were investigated. The addition of Ag NW further improved the sheet resistance of the PEDOT:PSS film, enhancing the performance of the silicon-organic hybrid solar cells. The present work using the low sheet resistance PEDOT:PSS layer paves the way to develop simple yet more efficient silicon-organic hybrid solar cells. - COLLAPSE
    PDFXMLCitation
    ReferencesInformation
    27 August 2024

  • Research Paper

    Improving the Cyclic Stability of Electrochromic Mirrors Composed of Gel Electrolyte

    겔 전해질로 구성된 전기변색 거울의 내구성 향상

    Ji-Hyeong Lee, Kwang-Mo Kang, Sang Bum Lee, Yoon-Chae Nah

    이지형, 강광모, 이상범, 나윤채

    The reversible metal electrodeposition (RME) process is used to prepare electrochromic mirrors with reflective-transparent optical states, by depositing metal particles on transparent … + READ MORE
    The reversible metal electrodeposition (RME) process is used to prepare electrochromic mirrors with reflective-transparent optical states, by depositing metal particles on transparent conductive substrates. These RME based devices can be used in smart windows to regulate indoor temperatures and light levels, serving dual purposes as lighting elements. Commercialization efforts are focused on achieving large-scale production, long-term durability, and a memory effect that maintains coloration without applied voltage. Enhancing durability has received particular attention, leading to the development of electrochromic mirrors that employ gel electrolytes, which are expected to reduce electrolyte leakage and improve mechanical stability compared to traditional liquid electrolyte devices. The gel electrolytes offer the additional advantage of various colors, by controlling the metal particle size and enabling smoother, denser formations. In this study, we investigated improving the durability of RME devices by adding polyvinyl butyral (PVB) to the liquid electrolyte and optimizing the concentration of PVB. Incorporating 10 % PVB resulted in excellent interfacial properties and superior electrochromic stability, with 92.6 % retention after 1,000 cycles. - COLLAPSE
    PDFXMLCitation
    ReferencesInformation
    27 August 2024
리스트형 보기썸네일형 보기
Journal Informaiton Korean Journal of Materials Research Korean Journal of Materials Research
Online Submission
  • scopus
  • NRF
  • KOFST
  • crossref crossmark
  • crossref cited-by
  • crosscheck
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close