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Andrew P. Grosvenor

Bio: Andrew P. Grosvenor is an academic researcher from University of Saskatchewan. The author has contributed to research in topics: XANES & X-ray photoelectron spectroscopy. The author has an hindex of 25, co-authored 99 publications receiving 5600 citations. Previous affiliations of Andrew P. Grosvenor include University of Western Ontario & McMaster University.


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 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: Atomic charges determined from the P 2p core line spectra and the fitted valence-band spectra support the approximate formulation M(1+)P(1-) for these phosphides, reaffirming the notion that these transition-metal phosphides have considerable metallic character.
Abstract: The binary transition-metal monophosphides CrP, MnP, FeP, and CoP have been studied with X-ray photoelectron spectroscopy. The shifts in phosphorus 2p3/2 core line binding energies relative to that...

390 citations

Journal ArticleDOI
TL;DR: In this article, the electronic structures of metal-rich binary phosphides M2P and M3P (M = Cr−Ni) have been examined by means of X-ray photoelectron and absorption spectroscopy and compared with those of the monophosphides MP.
Abstract: The electronic structures of metal-rich binary phosphides M2P and M3P (M = Cr−Ni) have been examined by means of X-ray photoelectron and absorption spectroscopy and compared with those of the monophosphides MP. The P 2p3/2 binding and P K-edge absorption energies decrease with greater ionic character of the M−P bonding and indicate the presence of anionic phosphorus, contrary to previous theoretical assertions but consistent with our previous results. Interatomic effects play a more important role in affecting the energy shifts in these metal-rich phosphides than in the monophosphides, becoming more pronounced with higher metal concentration. Although the M 2p3/2 XPS spectra show no discernible shifts in binding energies, they reveal satellite features whose intensity can be related to metal charge in the Co- and Ni-containing phosphides. In these cases, the metal charge becomes less positive with higher metal concentration. For Ni2P and Ni3P, this trend was confirmed from an analysis of the Ni L-edge and...

220 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


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: An overview of recent development of TMP nanomaterials as catalysts for hydrogen generation with high activity and stability is presented, and specific strategies to further improve the catalytic efficiency and stability of T MPs by structural engineering are demonstrated.
Abstract: The urgent need of clean and renewable energy drives the exploration of effective strategies to produce molecular hydrogen. With the assistance of highly active non-noble metal electrocatalysts, electrolysis of water is becoming a promising candidate to generate pure hydrogen with low cost and high efficiency. Very recently, transition metal phosphides (TMPs) have been proven to be high performance catalysts with high activity, high stability, and nearly ∼100% Faradic efficiency in not only strong acidic solutions, but also in strong alkaline and neutral media for electrochemical hydrogen evolution. In this tutorial review, an overview of recent development of TMP nanomaterials as catalysts for hydrogen generation with high activity and stability is presented. The effects of phosphorus (P) on HER activity, and their synthetic methods of TMPs are briefly discussed. Then we will demonstrate the specific strategies to further improve the catalytic efficiency and stability of TMPs by structural engineering. Making use of TMPs as cocatalysts and catalysts in photochemical and photoelectrochemical water splitting is also discussed. Finally, some key challenges and issues which should not be ignored during the rapid development of TMPs are pointed out. These strategies and challenges of TMPs are instructive for designing other high-performance non-noble metal catalysts.

2,104 citations

Journal ArticleDOI
TL;DR: The topotactic fabrication of self-supported nanoporous cobalt phosphide nanowire arrays on carbon cloth via low-temperature phosphidation of the corresponding Co(OH)F/CC precursor offers excellent catalytic performance and durability under neutral and basic conditions.
Abstract: In this Communication, we report the topotactic fabrication of self-supported nanoporous cobalt phosphide nanowire arrays on carbon cloth (CoP/CC) via low-temperature phosphidation of the corresponding Co(OH)F/CC precursor. The CoP/CC, as a robust integrated 3D hydrogen-evolving cathode, shows a low onset overpotential of 38 mV and a small Tafel slope of 51 mV dec–1, and it maintains its catalytic activity for at least 80 000 s in acidic media. It needs overpotentials (η) of 67, 100, and 204 mV to attain current densities of 10, 20, and 100 mA cm–2, respectively. Additionally, this electrode offers excellent catalytic performance and durability under neutral and basic conditions.

2,063 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