• Title/Summary/Keyword: Auger

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ZnO on Thiolated Graphene Oxide as Efficient Photocatalyst for Degradation of Methylene Blue

  • Kim, Yu Hyun;Choi, Hyun Chul
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3586-3590
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    • 2013
  • We present here an efficient and simple method for preparation of highly active heterogeneous ZnO photocatalyst (graphene oxide-zinc oxide: GO-ZnO), specifically by deposition of ZnO nanoparticles onto thiolated GOs. The resultant GO-ZnO sample was characterized by TEM, XRD, Auger, XPS, and Raman measurements, revealing that the size-similar and quasi-spherical ZnO nanoparticles were anchored to the thiolated GO surfaces. The average particle diameter was about 2.5 nm. In the photodegradation of methylene blue (MB) under ultraviolet (UV) light, GO-ZnO exhibited remarkably enhanced photocatalytic efficiency compared with thiolated GO and pure ZnO particles. This strong photocatalytic performance of GO-ZnO can be attributed to the suppression of electron recombination and the enhancement of mass transportation. The results showed that thiolated GO is the preferable supporting material.

A Study on the Cycle Life Improvement of V-Ti-Ni(V-rich) Alloy as a Negative Electrode for Ni/MH Rechargeable Battery (Ni/MH 2차전지의 음극으로써 V-Ti-Ni(V-rich) 수소저장합금의 전극수명 향상에 관한 연구)

  • Kim, Ju-Wan;Lee, Seong-Man;Lee, Jae-Yeong
    • Transactions of the Korean hydrogen and new energy society
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    • v.7 no.1
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    • pp.39-44
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    • 1996
  • The discharge capacity of V-Ti-Ni(V-rich) metal hydride electrode during the charge-discharge cycling was investigated in KOH electrolyte. All electrodes were degraded within 25 cycles. To investigate the cause of the degradation phenomena impedance measurements were performed by using E.I.S(electrochemical impedance spectroscopy). The surfaces of the degraded electrodes were examined by Auger electron spectroscopy (AES). It was observed that all electrodes were covered with oxygen from the surface to the bulk, titanium was enriched near surface, and vanadium was dissolved from the surface to the bulk.

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PHOSPHORUS NITRIDE FILMS ON InP SURFACE BY PHOTO-CVD (광CVD에 의한 InP기판 위에 질화인막의 성장)

  • Hong, Youg-Tae;Lee, Jae-Hak;Jeong, Yoon-Ha;Bae, Young-Ho;Kim, Kwang-Ill;Jeong, Wook-Jin
    • Proceedings of the KIEE Conference
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    • 1989.07a
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    • pp.386-389
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    • 1989
  • Phosphorus nitride films on InP surface were grown by a Photo-CVD (chemical vapor deposition) technique over 100-250 $^{\circ}C$ range of substrate temperature, which is based on direct photolysis of $PCl_3/H_2$ and $NH_3$ gas mixtures by 185nm ultraviolet light from a low pressure mercury lamp. The film growth rate ed the refractive index(n) were shown about 700-800 ${\AA}/hr$ and 1.7-1.8, respectively. Composition ratio and interface properties were analyzed by AES(Auger Electron Spectroscopy) and XPS (X-ray Photoelectron Spectorscopy) technique.

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Effect of a Laser Ablation for Carbon Nitride Film Deposition (고전압 방전 플라즈마에 의한 질화탄소 박막 층착 시 레이저 애블레이션 효과)

  • 김종일
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07a
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    • pp.240-243
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    • 2002
  • Carbon nitride films have been deposited on Si(100) substrate by a high voltage discharge plasma combined with laser ablation in a nitrogen atmosphere. The films were grown both with and without the Presence of an assisting focused Nd:YAG laser ablation. The laser ablation of the graphite target leads to vapor Plume plasma expending into the ambient nitrogen arc discharge area. X-ray photoelectron spectroscopy and Auger electron spectroscopy were used to identify the binding structure and the content of the nitrogen species in the deposited films. The surface morphology of the films was studied using a scanning electron microscopy Data of infrared spectroscopy and x-ray photoelectron spectroscopy indicate the existence of carbon-nitrogen bonds in the films. The x-ray diffraction measurements have also been taken to characterize the crystal properties of the obtain films.

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The Chemical COmposition Analysis by AES and XPS of PbTiO$_3$ Thin Films Fabricated by CVD (화학증착법에 의해 제조된 PbTiO$_3$ 박막의 AES와 XPS에 의한 조성분석)

  • Soon Gil Yoon;Ho Gi Kim
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1989.06a
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    • pp.83-86
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    • 1989
  • Lead titanate thin films with a perovskite structure were successfully structure were successfully fabricated on titanium substrate by Chemical Vapour Deposition(CVD). Analyses of Auger Electron Spectroscopy(AES) and X-ray Photoelectron Spectroscopy (XPS) have been performed in order to find a chemical composition of lead titanate films. The analysis of chemical composition by AES and XPS was investigated for variations of deposition temperature and Ti(C$_2$H$_{5}$O)$_4$ fractions. The chemical composition of PbTiO$_3$by XPS analysis was almost constant regardless of deposition parameters and the comparison of chemical composition by AES and XPS was performed.d.

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The Blue and Red Luminescences from Ambient Air Aged Porous Silicon

  • Chang, S.S;Yoon, S.O;Choi, G.J;Kawakami, Y;Sakai, A
    • The Korean Journal of Ceramics
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    • v.4 no.1
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    • pp.28-32
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    • 1998
  • This paper reports on photoluminescence (PL), luminescence decay curves, and compositional analysis of porous silicon(PS) which is aged under air ambient by Fourier transform infrared vibrational spectroscopy (FTIR) and by Auger electron spectroscopy (AES). Porous silicos which has been aged under air ambient yields two PL band structures, i.e. blue/violet PL and red PL. The evolution of a blue/violet band is pronounced, especially for thin PS film which is prepared in dilute HF solution. The blue/violet PL band has been observed initially to increrase rapidly with aging, then saturated with further atmospheric aging. The ambient air aged PS exhibits a fast decay time of sub-nanosecond at room temperature and shows appreciably faster decay time than that at 20K. Atmospheric aging of this thin blue/violet luminescing PS yield non-stoichiometric oxide judging from the vibrational spectra of Si-O and AES analysis.

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Improvement of Luminescence Degradation of Phosphor Screen by Surface Modification with $H_{3}PO_{4}$ Solution Treatment (인산 처리 공정에 의한 ZnS:Ag,Cl 형광막의 발광 열화특성의 개선)

  • Park, Zin-Min;Jeon, Duk-Young;Cha, Seung-Nam;Jin, Yong-Wan;Kim, Jong-Min
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.04b
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    • pp.49-52
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    • 2002
  • Degradation characteristics of cathodoluminescence (CL) of ZnS:Ag,Cl phosphor were investigated with measurements of CL and photoluminescence (PL). Phosphoric acid treatment was performed to phosphor particles in order to improve CL degradation of phosphor screen that occurred during panel sealing process, and we will discuss mechanisms of degradation and improvement of luminescence mainly with help of AES (auger electron spectroscopy) analysis.

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Annealing for Improving adhesion between Metal layer and Oxide layer (산화막과 금속박막 계면에서의 adhesion 개선을 위한 열처리)

  • 김응수
    • Proceedings of the IEEK Conference
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    • 2002.06b
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    • pp.225-228
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    • 2002
  • The adhesion effect between the oxide layer and the metal layer has been studied by RTP anneal. Two types of oxides, BPSG and P-TEOS, were used as a bottom layer under multi-layered metal film. We observe the interface between oxide and metal layer using SEM (scanning electron microscopy), TEM (transmission electron microscopy), AES (auger electron spectroscopy). Adhesion failure was occurred by interfacial reaction between the BPSG oxide and the multi-layered metal film at 650"C RTP anneal. The phosphorus rich layer was observed at interface between BPSG oxide and metal layer by AES and TEM measurements. On the other hand adhesion was a)ways good in the sample used P-TEOS oxide as a bottom layer. We have known that adhesion between BPSG and multi-layered metal film was improved when the sample was annealed below $650^{\circ}C$.TEX>.

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A Study on the Application of Anti-Corrosion Techniques on the Surface of Oxygen Free Copper (무산소동의 표면부식 방지기술 적용에 관한 연구)

  • Joo, Hyung-Goun;Lee, Dae-Young;Zhang, Da Quan;Lee, Kang-Yong;Al-Hanash, Essam Khamis Ibrahim
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.4
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    • pp.425-429
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    • 2009
  • The protection for copper tarnish was developed by surface treatment method and volatile corrosion inhibiting (VCI) technology. The performance of surface treatment and VCI material is also examined in simulated test environment. Benzotriazole (BTAH) solution that contained molybdate showed best performance than others. Usage of VCI materials with surface treatment was more effective. The protection film foamed on the surface of copper was investigated by auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS). Molybdate does not participate in the formation of the protective film but promotes the passivation effect. This facilitates the stabilization of the cuprous oxide film, and strengthens the adsorption of BTAH.

Tribological properties of mono/multilayer LB molecular films (단층/다층 LB 분자막의 트라이볼로지 특성)

  • ;;G.K. Zhavnerko
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.211-214
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    • 2003
  • The tribological properties of amphiphilic monolayers and composite multilayer on silicon surface were investigated using micro-tribometer and Auger Electron Spectroscopy. Langmuir-Blodgett (LB) monolayers from behenic acid. 2.4-heneicosanedione(HD) and its copper complex((HD)$_2$Cu) were fabricated on silicon surface and the composite multilayer of 5-bilayer of (HD)$_2$Cu was fabricated on the surface of octadecyltrichlorsilane (OTS) self-assembled monolayer(SAM). We observed that LB monolayers and the composite multilayer exhibited a steady and excellent friction response when compared with the OTS SAM. These LB mono and multilayer also showed much higher wear-resistance than the OTS SAM.

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