@article {1469,
	title = {Surface characterization of polytetrafluoroethylene (PTFE) transfer films during rolling-sliding tribology tests using X-ray photoelectron spectroscopy},
	journal = {Wear},
	volume = {261},
	number = {10},
	year = {2006},
	note = {ISI Document Delivery No.: 113XZTimes Cited: 4Cited Reference Count: 33Lu, X. Wong, K. C. Wong, P. C. Mitchell, K. A. R. Cotter, J. Eadie, D. T.},
	month = {Nov},
	pages = {1155-1162},
	type = {Article},
	abstract = {A disk-on-disk Amsler wear tester simulating the rolling-sliding motion and high pressure during wheel/rail contact, was used to study the wear performance of PTFE including its film transfer and material flow properties. The chemical composition of the transfer film formed on the wheel-disk surface at various test stages were analyzed by X-ray photoelectron spectroscopy (XPS). The friction curve of the PTFE films obtained on the Amsler can be divided into three regions, according to the friction level and disk surface morphology. Initially, there is a rapid increase of friction coefficient which is presumably accompanied by a fast material transfer from pre-coated rail-disk to the wheel-disk surfaces. In the second region, the friction remains stable throughout and the XPS results show the presence of PTFE on the wheel-disk surface which confirms a transfer of material between the two contact surfaces. In addition, the splitting of F 1s and C 1s photoelectron peaks of PTFE, as a result of a discrepancy in surface charging, suggests that the transfer film exists in two forms: thick patch and thin film. With an increase in rolling cycles, the thick patches become thinner, as well as its coverage reduces. By contrast, the thin film gains both in thickness and coverage. Using a simple model, the thin film is calculated to be only a few nanometers thick. At the beginning of the third region, only a thin film is left on the surface. Additional rolling leads to a rapid rise in friction and the transfer film thickness continues to decrease. The evidence supports the removal of PTFE out of the contact zone, and a high friction coefficient (mu = 0.6) is reached at the end of the test indicating an un-lubricated metal-metal contact. No major tribochemical reaction of PTFE is observed during this study. (c) 2006 Elsevier B.V. All rights reserved.},
	keywords = {(XPS), COMPOSITES, CONTACT, friction, friction modifier, INTERFACE, LUBRICATION, MODIFIER, polytetrafluoroethylene (PTFE), SURFACE, third body, TOP, WEAR, WHEEL-RAIL ADHESION, wheel/rail contact, X-ray photoelectron spectroscopy},
	isbn = {0043-1648},
	url = {<Go to ISI>://000242632600012},
	author = {Lu, X. and Wong, K. C. and Wong, P. C. and Mitchell, K. A. R. and Cotter, J. and Eadie, D. T.}
}
@article {798,
	title = {Titanium boron nitride films grown by ion beam assisted deposition: chemical and optical characterization},
	journal = {Surface \& Coatings Technology},
	volume = {183},
	number = {2-3},
	year = {2004},
	note = {ISI Document Delivery No.: 822CMTimes Cited: 4Cited Reference Count: 41},
	month = {May},
	pages = {369-377},
	type = {Article},
	abstract = {Titanium boron nitride films with a functionally graded underlayer of Ti/TiN were grown at low temperatures ( < 200 degreesC) on a silicon substrate using ion beam assisted deposition. These coatings had a total thickness of 1.5 +/- 0.2 mum. They were characterized using X-ray diffraction (XRD), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and spectroscopic ellipsometry. The primary phases in the film were identified using XRD and were found to be in agreement with the equilibrium phase diagram. The surface morphology and nanocrystalline nature of the coating were deduced using AFM. The chemical and phase composition was determined from XPS measurements. The refractive indices were deduced from the investigation of the ellipsometric data and were subsequently correlated to the elemental and phase composition. The hardness and elastic modulus were measured and were found to depend on phase composition. The films were implanted with carbon ions. XPS measurements revealed that new phases formed at the surface as a result of carbon implantation, namely, titanium carbide and elemental carbon. Carbon implantation significantly reduced the friction coefficient from 0.5-0.7 to 0.15-0.25. The hardness of the films decreased by 2-5\%. (C) 2003 Elsevier B.V. All rights reserved.},
	keywords = {B-N COATINGS, ellipsometry, HARD COATINGS, ion beam assisted deposition, MECHANICAL-PROPERTIES, nanocrystal, NITRIDE, SUPERHARD NANOCOMPOSITE COATINGS, THIN-FILMS, TIBXNY COATINGS, X-ray photoelectron spectroscopy},
	isbn = {0257-8972},
	url = {<Go to ISI>://000221512300031},
	author = {Aouadi, S. M. and Debessai, M. and Namavar, E. and Wong, K. C. and Mitchell, K. A. R.}
}
@article {5206,
	title = {XPS study of interfaces in a two-layer light-emitting diode made from PPV and Nafion with ionically exchanged Ru(bpy)(3)(2+)},
	journal = {Applied Surface Science},
	volume = {174},
	number = {1},
	year = {2001},
	note = {ISI Document Delivery No.: 416RQTimes Cited: 13Cited Reference Count: 39},
	month = {Apr},
	pages = {43-50},
	type = {Article},
	abstract = {X-ray photoelectron spectroscopy (XPS) was used to investigate the interfacial chemistries occurring in a prototype two-layer polymer light-emitting diode that had been fabricated from PPV and Nafion with ion-exchanged Ru(bpy)(3)(2 +) Magnesium and indium tin oxide (ITO) were used as electrodes, and XPS observations were made as the different layers were added sequentially. Specifically, Mg was deposited on a layer of Nafion with incorporated Ru(bpy)(3)(2 +), and this was itself deposited on PPV-coated ITO. The morphology of Nafion, which is dictated by the strongly hydrophilic and hydrophobic groups that compose it, is indicated to rearrange with the incorporation of Ru(bpy)(3)(2 +) this rearrangement appears reinforced when a thin film is deposited on PPV. The Mg deposition results in substantial changes in XPS spectra, in part due to a direct interaction with the fluorocarbon backbone of Nation. (C) 2001 Elsevier Science B.V. All rights reserved.},
	keywords = {CHEMISTRY, conjugated polymers, COPOLYMERS, ELECTROLUMINESCENCE, FILMS, luminescence, MEMBRANES, NAFION, POLYETHYLENETEREPHTHALATE, polymer light-emitting diodes, RAY PHOTOELECTRON-SPECTROSCOPY, ruthenium polypyridyl complex, SYSTEMS, X-ray photoelectron spectroscopy},
	isbn = {0169-4332},
	url = {<Go to ISI>://000167794300006},
	author = {Susac, D. and Kono, M. and Wong, K. C. and Mitchell, K. A. R.}
}
@article {4330,
	title = {XPS studies of the nitridation of MoO3 thin films on alumina and silica supports},
	journal = {Applied Surface Science},
	volume = {136},
	number = {3},
	year = {1998},
	note = {ISI Document Delivery No.: 140QWTimes Cited: 3Cited Reference Count: 40},
	month = {Nov},
	pages = {178-188},
	type = {Article},
	abstract = {X-ray photoelectron spectroscopy has been used to characterize thin films of MoO3 formed on planar oxidized supports, namely AlOx (from aluminum strip) and SiO2 (from silicon wafer). Comparisons are made with behaviour for MoO3 on metallic Mo substrate. It is observed that on calcination at 450 degrees C, the Mo 3d spectral features shift to higher binding energy for MoO3/AlOx and to lower binding energy for MoO3/SiO2, On nitridation by heating in NH3, it is found that the samples on the oxide supports show easier O-N replacement compared with the MoO3/Mo system. In general, the nitridation behaviour for MoO3/AlO, is similar to that of MoO3/Mo, but Mo species in MoO3/SiO2 seem to be more easily reduced (Mo(0) is detected for the SiO2 system but not for AlOx). Comparisons of heating rates for the second nitridation step from 350 to 450 degrees C were made for the MoO3/Mo and MoO3/AlOx samples. Differences between the high heating rate (100 K/h) and the low heating rate (40 K/h) are incremental but definite. The lower heating rate is favourable both for the O-N replacement and for the metal reduction. For example, more Mo(+3) is present after the nitridation to 450 degrees C when the low-heating rate regime is used, compared with that formed when the heating is done at the higher rate. (C) 1998 Elsevier Science B.V. All rights reserved.},
	keywords = {ADSORPTION, BEHAVIOR, CARBIDE, HYDRODENITROGENATION CATALYSTS, HYDRODESULFURIZATION, MOLYBDENUM NITRIDE, MoO3 thin films, nitridation, QUINOLINE, SITES, SURFACE-AREA, THIOPHENE, X-ray photoelectron, X-ray photoelectron spectroscopy},
	isbn = {0169-4332},
	url = {<Go to ISI>://000077100700002},
	author = {Leung, Y. L. and Wong, P. and Zhou, M. Y. and Mitchell, K. A. R. and Smith, K. J.}
}
@article {4331,
	title = {X-ray photoelectron spectroscopy studies of the reduction of MoO3 thin films by NH3},
	journal = {Applied Surface Science},
	volume = {136},
	number = {1-2},
	year = {1998},
	note = {ISI Document Delivery No.: 133ZGTimes Cited: 7Cited Reference Count: 33},
	month = {Oct},
	pages = {147-158},
	type = {Article},
	abstract = {X-ray photoelectron spectroscopy (XPS) has been used to gain insight into surface reaction pathways associated with the nitridation by NH3 of MoO3 thin films grown on metallic substrates. The samples formed can be seen as model hydrodenitrogenation (HDN) catalysts, but the more-controlled surface morphology allows spectral features to be studied in the absence of charging effects that can interfere with such measurements on high-area samples. Observed core level and valence spectra are consistent with the MoO3 being reduced, but the degree of reduction depends on the reaction temperature. Heating to 350 degrees C indicates some conversion to Mo(+5) and {\textquoteright}O-rich{\textquoteright} Mo(+4) components, while heating to 450 degrees C and to 700 degrees C give respectively a {\textquoteright}N-rich{\textquoteright} Mo(+4) form and a Mo(+3) oxynitride as the dominant components. It is concluded that the nitridation of MoO3 by NH3 involves initial hydrogenation, with subsequent elimination of water, and the effective replacement of O by N as the reduction continues. Surface compositions determined here during the nitridation process contrast with conclusions reached previously for the evolution of bulk phases as deduced by X-ray diffraction. (C) 1998 Elsevier Science B.V. All rights reserved.},
	keywords = {ADSORPTION, ammonia, Auger, CATALYSTS, DECOMPOSITION, HYDRODENITROGENATION, MOLYBDENUM NITRIDES, MOO3, NH3, REDUCTION, SURFACE-AREA, X-ray photoelectron spectroscopy, XPS},
	isbn = {0169-4332},
	url = {<Go to ISI>://000076717000022},
	author = {Leung, Y. L. and Wong, P. C. and Mitchell, K. A. R. and Smith, K. J.}
}
@article {3917,
	title = {Accurate density functional calculation of core electron binding energies .5. Application to nitriles. Model molecules for polyacrylonitrile revisited},
	journal = {Journal of Electron Spectroscopy and Related Phenomena},
	volume = {83},
	number = {2-3},
	year = {1997},
	note = {ISI Document Delivery No.: XC597Times Cited: 24Cited Reference Count: 30},
	month = {Feb},
	pages = {227-234},
	type = {Article},
	abstract = {A recent procedure for computing accurate core electron binding energies (CEBEs) via density functional theory (DFT) is applied to acetonitrile, propionitrile, 2-cyanopropane, acrylonitrile, methacrylonitrile and the 2-methylglutaronitrile conformer of lowest energy, The first three systems have been studied in the past as model compounds to interpret the XPS spectrum of polyacrylonitrile (PAN) using post-Hartree-Fock finite-difference calculations, in order to solve a controversy in the assignment of chemically shifted atoms in the C 1s region, This assignment is revisited with the unrestricted generalized transition-state model and a combined functional of Becke{\textquoteright}s 1988 exchange with Perdew{\textquoteright}s 1986 correlation. Using Dunning{\textquoteright}s correlation-consistent polarized valence triple zeta basis sets with scaling improvements, we obtain predicted CEBEs for gasphase acetonitrile, propionitrile and acrylonitrile in remarkable agreement with experiment (average absolute deviation 0.09 eV). The CEBEs of these systems confirm the overall trends of the previous attributions of their respective gas-phase XPS spectrum, except in the case of propionitrile. These results, as well as those on 2-cyanopropane, methacrylonitrile and 2-methylglutaronitrile, bring some additional information on the extrapolation of the results to the assignment of the C 1s contributions of polyacrylonitrile. (C) 1997 Elsevier Science B.V.},
	keywords = {APPROXIMATION, BASIS-SETS, computation, CORE LEVELS, density, functional theory, GAS-PHASE, NITRILES, POLYACRYLONITRILE, SPECTROSCOPY, X-ray photoelectron spectroscopy, XPS},
	isbn = {0368-2048},
	url = {<Go to ISI>://A1997XC59700014},
	author = {Bureau, C. and Chong, D. P. and Lecayon, G. and Delhalle, J.}
}
