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B. A. Kobe

Bio: B. A. Kobe is an academic researcher from University of Western Ontario. The author has contributed to research in topics: X-ray photoelectron spectroscopy & Oxide. The author has an hindex of 13, co-authored 18 publications receiving 2945 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the authors investigated the usefulness of calculated multiplet peaks to fit high-resolution iron 2p3/2 spectra from high-spin compounds. And they found that the multiplets were found to fit most spectra well, particularly when contributions attributed to surface peaks and shake-up satellites were included.
Abstract: Ferrous (Fe2+) and ferric (Fe3+) compounds were investigated by XPS to determine the usefulness of calculated multiplet peaks to fit high-resolution iron 2p3/2 spectra from high-spin compounds. The multiplets were found to fit most spectra well, particularly when contributions attributed to surface peaks and shake-up satellites were included. This information was useful for fitting of the complex Fe 2p3/2 spectra for Fe3O4 where both Fe2+ and Fe3+ species are present. It was found that as the ionic bond character of the iron —ligand bond increased, the binding energy associated with either the ferrous or ferric 2p3/2 photoelectron peak also increased. This was determined to be due to the decrease in shielding of the iron cation by the more increasingly electronegative ligands. It was also observed that the difference in energy between a high-spin iron 2p3/2 peak and its corresponding shake-up satellite peak increased as the electronegativity of the ligand increased. The extrinsic loss spectra for ion oxides are also reported; these are as characteristic of each species as are the photoelectron peaks. Copyright © 2004 John Wiley & Sons, Ltd.

2,637 citations

Journal ArticleDOI
TL;DR: In this article, the authors used X-ray photoelectron spectroscopy (XPS) and QUASES TM to study the oxidation of Fe by water (H2O) vapour and found that the oxide formed at 25 and 150 C was thinner than that formed when oxygen (O2) gas was present.

205 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used XP spectra and QUASES TM Analyze and Generate software programs to investigate the kinetics of the overall reaction and found that the oxide films produced after short oxygen exposure times contained a mixture of magnetite (Fe3O4) and maghemite (c-Fe2O3) without distinct interfaces between the two being seen.

117 citations

Journal ArticleDOI
TL;DR: Three-dimensional printing was used to fabricate various metallic structures by directly integrating a Br-containing vinyl-terminated initiator into the 3D resin followed by surface-initiated atomic-transfer radical polymerization (ATRP) and subsequent electroless plating.
Abstract: Three-dimensional printing was used to fabricate various metallic structures by directly integrating a Br-containing vinyl-terminated initiator into the 3D resin followed by surface-initiated atomic-transfer radical polymerization (ATRP) and subsequent electroless plating. Cu- and Ni-coated complex structures, such as microlattices, hollow balls, and even Eiffel towers, were prepared. Moreover, the method is also capable of fabricating ultralight cellular metals with desired structures by simply etching the polymer template away. By combining the merits of 3D printing in structure design with those of ATRP in surface modification and polymer-assisted ELP of metals, this universal, robust, and cost-effective approach has largely extended the capability of 3D printing and will make 3D printing technology more practical in areas of electronics, acoustic absorption, thermal insulation, catalyst supports, and others.

97 citations

Journal ArticleDOI
TL;DR: The feasible i3DP makes 3D printed complex architectures possible for nearly any desired surface modification for various applications, for example, even pouring water into a sieve was readily achieved.

92 citations


Cited by
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Journal ArticleDOI
TL;DR: Biesinger et al. as mentioned in this paper proposed a more consistent and effective approach to curve fitting based on a combination of standard spectra from quality reference samples, a survey of appropriate literature databases and/or a compilation of literature references and specific literature references where fitting procedures are available.

7,498 citations

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the usefulness of calculated multiplet peaks to fit high-resolution iron 2p3/2 spectra from high-spin compounds. And they found that the multiplets were found to fit most spectra well, particularly when contributions attributed to surface peaks and shake-up satellites were included.
Abstract: Ferrous (Fe2+) and ferric (Fe3+) compounds were investigated by XPS to determine the usefulness of calculated multiplet peaks to fit high-resolution iron 2p3/2 spectra from high-spin compounds. The multiplets were found to fit most spectra well, particularly when contributions attributed to surface peaks and shake-up satellites were included. This information was useful for fitting of the complex Fe 2p3/2 spectra for Fe3O4 where both Fe2+ and Fe3+ species are present. It was found that as the ionic bond character of the iron —ligand bond increased, the binding energy associated with either the ferrous or ferric 2p3/2 photoelectron peak also increased. This was determined to be due to the decrease in shielding of the iron cation by the more increasingly electronegative ligands. It was also observed that the difference in energy between a high-spin iron 2p3/2 peak and its corresponding shake-up satellite peak increased as the electronegativity of the ligand increased. The extrinsic loss spectra for ion oxides are also reported; these are as characteristic of each species as are the photoelectron peaks. Copyright © 2004 John Wiley & Sons, Ltd.

2,637 citations

Journal ArticleDOI
TL;DR: In this paper, a scheme for fitting the Ni 2p spectra using multiplet envelopes is proposed, based on charge transfer assignments of the main peak at 854.6 eV and the broad satellite centred at around 861 eV to the cd 9 L and the unscreened cd 8 final state configurations, respectively.

1,589 citations

Journal ArticleDOI
TL;DR: In this paper, an approach based on standard spectra from quality reference samples (Ni, NiO, Ni(OH)2, NiOOH), subtraction of these spectra, and data analysis that integrates information from the Ni 2p spectrum and the O 1s spectra is demonstrated.
Abstract: Quantitative chemical state X-ray photoelectron spectroscopic analysis of mixed nickel metal, oxide, hydroxide and oxyhydroxide systems is challenging due to the complexity of the Ni 2p peak shapes resulting from multiplet splitting, shake-up and plasmon loss structures. Quantification of mixed nickel chemical states and the qualitative determination of low concentrations of Ni(III) species are demonstrated via an approach based on standard spectra from quality reference samples (Ni, NiO, Ni(OH)2, NiOOH), subtraction of these spectra, and data analysis that integrates information from the Ni 2p spectrum and the O 1s spectra. Quantification of a commercial nickel powder and a thin nickel oxide film grown at 1-Torr O2 and 300 °C for 20 min is demonstrated. The effect of uncertain relative sensitivity factors (e.g. Ni 2.67 ± 0.54) is discussed, as is the depth of measurement for thin film analysis based on calculated inelastic mean free paths. Copyright © 2009 John Wiley & Sons, Ltd.

1,215 citations

Journal ArticleDOI
TL;DR: In this article, the authors extend and extend previously published X-ray photoelectron spectroscopy curve-fitting and data analysis procedures for a wide range of copper containing species.
Abstract: Chemical state X-ray photoelectron spectroscopic analysis of copper species is challenging because of the complexity of the 2p spectra resulting from shake-up structures for Cu(II) species and overlapping binding energies for Cu metal and Cu(I) species. This paper builds upon and extends previously published X-ray photoelectron spectroscopy curve-fitting and data analysis procedures for a wide range of copper containing species. Steps undertaken include the following: (i) an examination of existing Cu 2p3/2 main peak and Cu 2p3/2 – Cu L3M4,5M4,5 Auger parameter literature data, (ii) analysis of a series of quality standard samples, (iii) curve-fitting procedures for both the Cu 2p3/2 and the Cu L3M4,5M4,5 spectra (as well as associated anions), (iv) calculations that determine the amount of Cu(II) species in a mixed oxidation state system, (v) calculations and necessary data for thin film mixed oxide/hydroxide thickness measurements, and (vi) a presentation of literature and standard sample values in a Wagner (chemical state) plot. Copyright © 2017 John Wiley & Sons, Ltd.

917 citations