• Title/Summary/Keyword: Vacuum Adsorption

Search Result 301, Processing Time 0.037 seconds

Dissociative adsorption structure of guanine on Ge(100)

  • Youn, Young-Sang;Kim, Do Hwan;Lee, Hye Jin;Kim, Sehun
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2015.08a
    • /
    • pp.109.1-109.1
    • /
    • 2015
  • Understanding the reaction mechanisms and structures underlying the adsorption of biomolecules on semiconductors is important for functionalizing semiconductor surfaces for various bioapplications. Herein, we describe the characteristic behavior of a primary nucleobase adsorbed on the semiconductor Ge(100). The adsorption configuration of guanine, a primary nucleobase found in DNA and RNA, on the semiconductor Ge(100) at an atomic level was investigated using scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. When adsorbed on Ge(100) at room temperature, guanine appears dark in STM images, indicating that the adsorption of guanine on Ge(100) occurs through N-H dissociation. In addition, DFT calculations revealed that "N(1)-H dissociation through an O dative bonded structure" is the most favorable adsorption configuration of all the possible ones. We anticipate that the characterization of guanine adsorbed on Ge(100) will contribute to the development of semiconductor-based biodevices.

  • PDF

ZnO/SiO2 Prepared by Atomic Layer Deposition as Adsorbents of Organic Dye in Aqueous Solution and Its Photocatalytic Regeneration

  • Jeong, Bora;Jeong, Myung-Geun;Park, Eun Ji;Seo, Hyun Ook;Kim, Dae Han;Yoon, Hye Soo;Cho, Youn Kyoung;Kim, Young Dok
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.167.2-167.2
    • /
    • 2014
  • In this work, ZnO shell on mesoporous $SiO_2$ ($ZnO/SiO_2$) was prepared by atomic layer deposition (ALD). Diethylzinc (DEZ) and $H_2O$ were used as precursor of ZnO shell. $ZnO/SiO_2$ sample was characterized by X-ray diffraction (XRD), N2 sorption isotherms, X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR). $ZnO/SiO_2$ showed higher adsorption capacity of MB than that of bare mesoporous $SiO_2$ and the adsorption capacities of $ZnO/SiO_2$ could be regenerated by UV exposure through the photocatalytic degradation of the adsorbed MB. This system could be used for removing organic dye from water by adsorption and reused after saturation of adsorption due to its photocatalytic regeneration.

  • PDF

Effects of Plasma on the Surface of Protein Chip Plates (단백질 칩 기판의 플라즈마 효과)

  • Hyun, J.W.;Kim, N.Y.
    • Journal of the Korean Vacuum Society
    • /
    • v.17 no.6
    • /
    • pp.549-554
    • /
    • 2008
  • Nickel Chloride coated protein chip plates were developed by using a spin coating method after $H_2$ plasma treatment. The adsorption ability of histidine tagged protein was investigated at various times of plasma treatment. The properties of the nickel chloride and protein on the surface of the slides were assayed using particle size analysis and the extent of the protein adsorption was determined by using a bio imaging analyzer system. The results show that the ability of protein adsorption decreased as increasing the time of $H_2$ plasma treatment. The mechanism on the ability of protein adsorption at the plate surface is discussed on results and discussions. The results also suggest that the surface stabilization of protein chip plates treated by plasma technology may be applicable in biosensor markets.