• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.402.2-402.2
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• 2016

In photoelectrochemical (PEC) water splitting, Cu2ZnSnS4 (CZTS) compound has attracted intense attention as a photocathode due to not only large optical absorption coefficient, but also earth-abundance of constituent elements and suitable band alignment. With rapid development of nanotechnology, one-dimensional nanostructures of CZTS have been investigated as a potential form to achieve high efficiency because the nanostructures are expected to be capable of capturing more light and enhancing charge separation and transport. Here, we report a well-controlled fabrication route for vertically-aligned CZTS nanorod arrays on anodic aluminium oxide (AAO) template via simple sol-gel process followed by deposition of ZnS or CdS buffer layers on the CZTS nanorod to enhance charge separation. The structure, morphology, composition, optical absorption, and PEC properties of the resulting CZTS nanorod samples were characterized using X-ray diffraction, Raman spectroscopy, transmission electron microscopy, energy dispersive X-ray spectrometry, scanning electron microscopy, and UV-vis spectroscopy.

• Transactions on Electrical and Electronic Materials
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• 제16권6호
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• pp.346-350
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• 2015

In this study, we carried out an investigation of the etch characteristics of TiO₂ thin films and the selectivity of TiO₂ to SiO₂ in adaptive coupled C1₂/Ar plasma. The maximum etch rate of the TiO₂ thin film was 136±5 nm/min at a gas mixing ratio of C1₂/Ar (75%:25%). The X-ray photoelectron spectroscopy (XPS) analysis showed the efficient destruction of oxide bonds by the ion bombardment as well as the accumulation of low volatile reaction products on the etched surface.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.117-117
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• 2015

Availability of X-ray photoelectron spectroscopy (XPS) for the identification of ionic liquids (ILs) was tested. Commercially available ionic liquids (1-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM] $BF_4$), (1-butyl-3-methyl imidazolium trifluoromethanesulfonate ([BMIM] OTf), (1-butyl-3-methyl imidazolium hexafluorophosphate ([BMIM] $PF_6$), 1-hexyl-3-imidazolium hexafluorophosphate ([HMIM] $PF_6$), and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM] $Tf_2N$) were qualitatively and semi-quantitatively analyzed with XPS. In order to confirm whether the results of XPS were correct, conventional method such as a nuclear magnetic resonance (NMR) was performed. After the XPS results were convinced by NMR, we synthesized ILs (1-(4-sulfonic acid) butyl-3-butylimidazolium trifluoromethanesulfonate ([SBBIM] OTf), 1-(4-sulfonic acid) propyl-3-methylimidazolium trifluoromethanesulfonate ([SPMIM] OTf), and 1-(4-sulfonic acid) propyl-3-butylimidazolium trifluoromethanesulfonate ([SPBIM] OTf) and analyzed it with XPS and NMR as well. It was successful the usage of XPS to analyze ILs without any purification processes.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.158.1-158.1
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• 2011

In this work, we prepared ultramicroporous carbons (UC) prepared by pyrolyzing poly(vinylidene fluoride) with different carbonization temperatures, and investigated the hydrogen storage behaviors. The surface functional groups and specific elements of UC were confirmed by Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), respectively. Textural properties were analyzed using $N_2$ adsorption isotherms at 77 K. The hydrogen storage capacity of the UC samples were investigated by BEL-HP at 298 K/10 MPa. From the results, it was found that the hydrogen storage capacity was enhanced with increasing of specific surface area, resulting from the formation of ultramicropore on the UC.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1287-1292
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• 2013

Extracellular biogenic synthesis of silver nanoparticles with various shapes using the rice bacterial blight bacterium Xanthomonas oryzae pv. oryzae BXO8 is reported. The synthesized silver nanoparticles were characterized by UV-Vis spectroscopy, powder X-ray diffractometry (XRD), scanning electron microscopy, energy dispersive X-ray spectrometry, and high-resolution transmission electron microscopy (HR-TEM). Based on the evidence of HR-TEM, the synthesized particles were found to be spherical, with anisotropic structures such as triangles and rods, with an average size of 14.86 nm. The crystalline nature of silver nanoparticles was evident from the bright circular spots in the SAED pattern, clear lattice fringes in the high-resolution TEM images, and peaks in the XRD pattern. The FTIR spectrum showed that biomolecules containing amide and carboxylate groups are involved in the reduction and stabilization of the silver nanoparticles. Using such a biological method for the synthesis of silver nanoparticles is a simple, viable, cost-effective, and environmentally friendly process, which can be used in antimicrobial therapy.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권3호
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• pp.109-115
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• 2003

Diamond-like carbon (DLC) films are deposited at room temperature using a filtered cathodic vacuum arc (FCVA) technique. The influence of negative bias voltage (applied to the substrate from 0 to -250V) on the $sp^3$ hybridized carbon fraction is examined by Raman spectroscopy and x-ray photoelectron spectroscopy (XPS) for C 1s core peak. For the first time, depth profile of C 1s, Si 2p, and O 1s XPS peaks for the deposited DLC film are obtained. DLC film is modeled as a multilayered structure. composing of surface, bulk, and interface. In addition, the x-ray reflectivity (XRR) is proposed as a method for estimating the density, surface roughness, and thickness of each layer constituting the DLC film. The estimated thickness of DLC film is in good agreement with the result obtained from the transmission electron microscope (TEM) measurement.

• 한국전기전자재료학회논문지
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• 제14권10호
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• pp.835-844
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• 2001

In this paper, we report the successful growth of crystalline carbon nitride films in Si(100) by a laser-electric discharge method. The laser ablation of the target leads to vapor plume plasma expending into the ambient nitrogen arc discharge area. X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy(AES) were used to identify the binding structure and the content of the nitrogen species in the deposited films. The surface morphology of the films with a deposition time of 2 hours is studied using a scanning electron microscopy (SEM). In order to determine the structural crystalline parameters, X-ray diffraction (XRD) was used to analysis the grown films.

• Transactions on Electrical and Electronic Materials
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• 제6권4호
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• pp.164-168
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• 2005

Effects of high-temperature slurry were investigated on the chemical mechanical polishing (CMP) performance of tetra-ethyl ortho-silicate (TEOS) film with silica and ceria slurries by the surface analysis of X-ray photoelectron spectroscopy (XPS). The pH showed a slight tendency to decrease with increasing slurry temperature, which means that the hydroxyl $(OH^-)$ groups increased in slurry as the slurry temperature increased and then they diffused into the TEOS film. The surface of TEOS film became hydro-carbonated by the diffused hydroxyl groups. The hydro-carbonated surface of TEOS film could be removed more easily. Consequently, the removal rate of TEOS film improved dramatically with increasing slurry temperature.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.372-373
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• 2006

Chemical kinetics affects Cu CMP results (removal rate, Non uniformity etc.) Because Cu is removed by chemical action. Key factors in chemical kinetics are process temperature and concentration of slurry components. In this study, Hydrogen peroxide and citric acid were selected as a oxidant and a complexing agent and Slurry were made by mixing this components. In order to study effects of Chemical Kinetics, X-ray photoelectron spectroscopy (XPS) were performed on Cu sample after etching test as concentration of citric acid and slurry temperature. Finally Cu CMP was performed as same conditions.

• Transactions on Electrical and Electronic Materials
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• 제16권5호
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• pp.274-279
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• 2015

Reduced graphite oxides (rGOs) were prepared by the common graphite oxidation method and the subsequent reductions. The reduction of graphite oxides (GOs) was conducted chemically and/or thermally. To further reduce the as-prepared rGOs, GOs were treated with chemical/thermal reductions or thermal/chemical reductions, in which the reduction sequence was also considered. The structural changes of as-prepared rGOs, depending on reduction methods, were investigated by X-ray diffraction analyses, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. In addition, we discuss the structural change of the rGOs and their closely related physical and electrical properties, such as thermogravimetry, nitrogen adsorption isotherm, and sheet resistance.