1
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Artmann E, Forschner L, Schüttler KM, Al-Shakran M, Jacob T, Engstfeld AK. Nanoporous Au Formation on Au Substrates via High Voltage Electrolysis. Chemphyschem 2023; 24:e202200645. [PMID: 36328970 DOI: 10.1002/cphc.202200645] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/27/2022] [Indexed: 11/06/2022]
Abstract
Nanoporous Au (NPG) films have promising properties, making them suitable for various applications in (electro)catalysis or (bio)sensing. Tuning the structural properties, such as the pore size or the surface-to-volume ratio, often requires complex starting materials such as alloys, multiple synthesis steps, lengthy preparation procedures or a combination of these factors. Here we present an approach that circumvents these difficulties, enabling for a rapid and controlled preparation of NPG films starting from a bare Au electrode. In a first approach a Au oxide film is prepared by high voltage (HV) electrolysis in a KOH solution, which is then reduced either electrochemically or in the presence of H2 O2 . The resulting NPG structures and their electrochemically active surface areas strongly depend on the reduction procedure, the concentration and temperature of the H2 O2 -containing KOH solution, as well as the applied voltage and temperature during HV electrolysis. Secondly, the NPG film can be prepared directly by applying voltages that result in anodic contact glow discharge electrolysis (aCGDE). By carefully adjusting the corresponding parameters, the surface area of the final NPG film can be specifically controlled. The structural properties of the electrodes are investigated by means of XPS, SEM and electrochemical methods.
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Affiliation(s)
- Evelyn Artmann
- Institute of Electrochemistry, Ulm University, D-89081, Ulm, Germany
| | - Lukas Forschner
- Institute of Electrochemistry, Ulm University, D-89081, Ulm, Germany
| | | | | | - Timo Jacob
- Institute of Electrochemistry, Ulm University, D-89081, Ulm, Germany
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2
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Rankine CD, Penfold TJ. Accurate, affordable, and generalizable machine learning simulations of transition metal x-ray absorption spectra using the XANESNET deep neural network. J Chem Phys 2022; 156:164102. [PMID: 35490005 DOI: 10.1063/5.0087255] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The affordable, accurate, and generalizable prediction of spectroscopic observables plays a key role in the analysis of increasingly complex experiments. In this article, we develop and deploy a deep neural network-XANESNET-for predicting the lineshape of first-row transition metal K-edge x-ray absorption near-edge structure (XANES) spectra. XANESNET predicts the spectral intensities using only information about the local coordination geometry of the transition metal complexes encoded in a feature vector of weighted atom-centered symmetry functions. We address in detail the calibration of the feature vector for the particularities of the problem at hand, and we explore the individual feature importance to reveal the physical insight that XANESNET obtains at the Fe K-edge. XANESNET relies on only a few judiciously selected features-radial information on the first and second coordination shells suffices along with angular information sufficient to separate satisfactorily key coordination geometries. The feature importance is found to reflect the XANES spectral window under consideration and is consistent with the expected underlying physics. We subsequently apply XANESNET at nine first-row transition metal (Ti-Zn) K-edges. It can be optimized in as little as a minute, predicts instantaneously, and provides K-edge XANES spectra with an average accuracy of ∼±2%-4% in which the positions of prominent peaks are matched with a >90% hit rate to sub-eV (∼0.8 eV) error.
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Affiliation(s)
- C D Rankine
- Chemistry-School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, United Kingdom
| | - T J Penfold
- Chemistry-School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, United Kingdom
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3
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Berger G, Wach A, Sá J, Szlachetko J. Reduction Mechanisms of Anticancer Osmium(VI) Complexes Revealed by Atomic Telemetry and Theoretical Calculations. Inorg Chem 2021; 60:6663-6671. [PMID: 33871984 DOI: 10.1021/acs.inorgchem.1c00467] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Resonant X-ray emission spectroscopy (RXES) has developed in the past decade as a powerful tool to probe the chemical state of a metal center and in situ study chemical reactions. We have used it to monitor spectral changes associated with the reduction of osmium(VI) nitrido complexes to the osmium(III) ammine state by the biologically relevant reducing agent, glutathione. RXES difference maps are consistent with the proposed DFT mechanism and the formation of two stable osmium(IV) intermediates, thereby supporting the overall pathway for the reduction of these high-valent anticancer metal complexes for which reduction by thiols within cells may be essential to the antiproliferative activity.
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Affiliation(s)
- Gilles Berger
- Microbiology, Bioorganic & Macromolecular Chemistry, Faculty of Pharmacy, Université Libre de Bruxelles, 1050 Brussels, Belgium.,Harvey Cushing Neuro-Oncology Laboratories, Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States.,Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Anna Wach
- Institute of Nuclear Physics, Polish Academy of Sciences, 31342 Krakow, Poland
| | - Jacinto Sá
- Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland.,Physical Chemistry Division, Department of Chemistry, Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden
| | - Jakub Szlachetko
- Institute of Nuclear Physics, Polish Academy of Sciences, 31342 Krakow, Poland
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4
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Wach A, Błachucki W, Czapla-Masztafiak J, Abreu Fernandes DL, Banaś D, Wojtaszek K, Tyrala K, Kwiatek WM, Sá J, Szlachetko J. In situ observation of charge transfer and crystal field formation via high energy resolution X-ray spectroscopy during temperature programmed oxidation. Phys Chem Chem Phys 2020; 22:14731-14735. [PMID: 32578618 DOI: 10.1039/d0cp01974g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, it has been demonstrated how resonant X-ray emission spectroscopy can be employed to study the charge transfer dynamics in real-time during the temperature-induced oxidation of metallic tungsten. Application of high energy resolution schemes allowed distinguishing charge transfer to separate orbitals resulting from crystal field splitting. Based on the time-resolved studies, it was possible to determine the corresponding charge transfer rates. From the experimental data, we determined that the electron transfer during the thermal oxidation of the metal dominates in the temperature range of 470-570 °C, reaching a maximum of 0.036 electrons per °C.
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Affiliation(s)
- Anna Wach
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
| | - Wojciech Błachucki
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
| | | | - Daniel Luis Abreu Fernandes
- Physical Chemistry Division, Department of Chemistry, Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden.
| | - Dariusz Banaś
- Institute of Physics, Jan Kochanowski University, Swietokrzyska 15, 25-406 Kielce, Poland
| | - Klaudia Wojtaszek
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
| | - Krzysztof Tyrala
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
| | - Wojciech M Kwiatek
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
| | - Jacinto Sá
- Physical Chemistry Division, Department of Chemistry, Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden. and Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - Jakub Szlachetko
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
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5
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Wach A, Sá J, Szlachetko J. Comparative study of the around-Fermi electronic structure of 5d metals and metal-oxides by means of high-resolution X-ray emission and absorption spectroscopies. JOURNAL OF SYNCHROTRON RADIATION 2020; 27:689-694. [PMID: 32381769 PMCID: PMC7206549 DOI: 10.1107/s1600577520003690] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 03/12/2020] [Indexed: 06/11/2023]
Abstract
The composition of occupied and unoccupied electronic states in the vicinity of Fermi energies is vital for all materials and relates to their physical, chemical and mechanical properties. This work demonstrates how the combination of resonant and non-resonant X-ray emission spectroscopies supplemented with theoretical modelling allows for quantitative analysis of electronic states in 5d transition metal and metal-oxide materials. Application of X-rays provides element selectivity that, in combination with the penetrating properties of hard X-rays, allows determination of the composition of electronic states under working conditions, i.e. non-vacuum environment. Tungsten metal and tungsten oxide are evaluated to show the capability to simultaneously assess composition of around-band-gap electronic states as well as the character and magnitude of the crystal field splitting.
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Affiliation(s)
- Anna Wach
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Jacinto Sá
- Physical Chemistry Division, Department of Chemistry, Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden
- Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - Jakub Szlachetko
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
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6
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Zeeshan F, Hoszowska J, Loperetti-Tornay L, Dousse JC. In-house setup for laboratory-based x-ray absorption fine structure spectroscopy measurements. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:073105. [PMID: 31370460 DOI: 10.1063/1.5094873] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 07/06/2019] [Indexed: 06/10/2023]
Abstract
We report on a laboratory-based facility for in-house x-ray absorption fine structure (XAFS) measurements. The device consists of a conventional x-ray source for the production of the incident polychromatic radiation and a von Hamos bent crystal spectrometer for the analysis of the incoming and transmitted radiation. The reliability of the laboratory-based setup was evaluated by comparing the Cu K-edge and Ta L3-edge XAFS spectra obtained in-house with the corresponding spectra measured at a synchrotron radiation facility. To check the accuracy of the device, the K- and L-edge energies and the attenuation coefficients below and above the edges of several 3d, 4d, and 5d elements were determined and compared with the existing experimental and theoretical data. The dependence of the XAFS spectrum shape on the oxidation state of the sample was also probed by measuring inhouse the absorption spectra of metallic Fe and two Fe oxides (Fe2O3 and Fe3O4).
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Affiliation(s)
- F Zeeshan
- Physics Department, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - J Hoszowska
- Physics Department, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - L Loperetti-Tornay
- Physics Department, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - J-Cl Dousse
- Physics Department, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
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7
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Lee T, Lee YJ, Palotás K, Lee G, Stampfl C, Soon A. Polymorphic expressions of ultrathin oxidic layers of Mo on Au(111). NANOSCALE 2019; 11:6023-6035. [PMID: 30869099 DOI: 10.1039/c8nr10278c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Ultrathin oxidic layers of Mo (i.e. O/Mo) on the Au(111) substrate are investigated using first-principles density-functional theory calculations. Various polymorphic structural models of these O/Mo layers are proposed and compared with previous experimental results - covering both spectroscopic and microscopic approaches of characterization. We find that, through the control of metal-oxygen coordination in these ultrathin oxidic O/Mo films on Au(111), the oxidation state of Mo atoms in the O/Mo layers can be modulated and reduced without intentional creation of oxygen vacancies. This is also assisted by a charge transfer mechanism from the Au substrate to these oxidic films, providing a direct means to tune the surface electronic properties of ultrathinoxide films on metal substrates.
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Affiliation(s)
- Taehun Lee
- Department of Materials Science & Engineering and Center for Artificial Synesthesia Materials Discovery, Yonsei University, Seoul 03722, Republic of Korea.
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8
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Błachucki W, Kayser Y, Czapla-Masztafiak J, Guo M, Juranić P, Kavčič M, Källman E, Knopp G, Lundberg M, Milne C, Rehanek J, Sá J, Szlachetko J. Inception of electronic damage of matter by photon-driven post-ionization mechanisms. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2019; 6:024901. [PMID: 31041363 PMCID: PMC6450797 DOI: 10.1063/1.5090332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 03/21/2019] [Indexed: 05/30/2023]
Abstract
"Probe-before-destroy" methodology permitted diffraction and imaging measurements of intact specimens using ultrabright but highly destructive X-ray free-electron laser (XFEL) pulses. The methodology takes advantage of XFEL pulses ultrashort duration to outrun the destructive nature of the X-rays. Atomic movement, generally on the order of >50 fs, regulates the maximum pulse duration for intact specimen measurements. In this contribution, we report the electronic structure damage of a molecule with ultrashort X-ray pulses under preservation of the atoms' positions. A detailed investigation of the X-ray induced processes revealed that X-ray absorption events in the solvent produce a significant number of solvated electrons within attosecond and femtosecond timescales that are capable of coulombic interactions with the probed molecules. The presented findings show a strong influence on the experimental spectra coming from ionization of the probed atoms' surroundings leading to electronic structure modification much faster than direct absorption of photons. This work calls for consideration of this phenomenon in cases focused on samples embedded in, e.g., solutions or in matrices, which in fact concerns most of the experimental studies.
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Affiliation(s)
- W. Błachucki
- Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - Y. Kayser
- Physikalisch-Technische Bundesanstalt, 10587 Berlin, Germany
| | | | - M. Guo
- Department of Chemistry–Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden
| | - P. Juranić
- Paul Scherrer Institute, CH-5232 Villigen-PSI, Switzerland
| | - M. Kavčič
- Jozef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - E. Källman
- Department of Chemistry–Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden
| | - G. Knopp
- Paul Scherrer Institute, CH-5232 Villigen-PSI, Switzerland
| | - M. Lundberg
- Department of Chemistry–Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden
| | - C. Milne
- Paul Scherrer Institute, CH-5232 Villigen-PSI, Switzerland
| | - J. Rehanek
- Paul Scherrer Institute, CH-5232 Villigen-PSI, Switzerland
| | - J. Sá
- Authors to whom correspondence should be addressed:; ; and
| | - J. Szlachetko
- Institute of Nuclear Physics, Polish Academy of Sciences, 31-342 Kraków, Poland
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9
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Wojtaszek K, Wach A, Czapla-Masztafiak J, Tyrala K, Sá J, Yıldız Özer L, Garlisi C, Palmisano G, Szlachetko J. The influence of nitrogen doping on the electronic structure of the valence and conduction band in TiO 2. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:145-151. [PMID: 30655479 DOI: 10.1107/s1600577518016685] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 11/23/2018] [Indexed: 06/09/2023]
Abstract
X-ray emission spectroscopy (XES) and X-ray absorption spectroscopy (XAS) provide a unique opportunity to probe both the highest occupied and the lowest unoccupied states in matter with bulk sensitivity. In this work, a combination of valence-to-core XES and pre-edge XAS techniques are used to determine changes induced in the electronic structure of titanium dioxide doped with nitrogen atoms. Based on the experimental data it is shown that N-doping leads to incorporation of the p-states on the occupied electronic site. For the conduction band, a decrease in population of the lowest unoccupied d-localized orbitals with respect to the d-delocalized orbitals is observed. As confirmed by theoretical calculations, the N p-states in TiO2 structure are characterized by higher binding energy than the O p-states which gives a smaller value of the band-gap energy for the doped material.
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Affiliation(s)
- Klaudia Wojtaszek
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Anna Wach
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | | | - Krzysztof Tyrala
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Jacinto Sá
- Department of Chemistry, Uppsala University, Uppsala, Sweden
| | - Lütfiye Yıldız Özer
- Department of Chemical Engineering, Khalifa University of Science and Technology, PO Box 54224, Masdar City, Abu Dhabi, United Arab Emirates
| | - Corrado Garlisi
- Department of Chemical Engineering, Khalifa University of Science and Technology, PO Box 54224, Masdar City, Abu Dhabi, United Arab Emirates
| | - Giovanni Palmisano
- Department of Chemical Engineering, Khalifa University of Science and Technology, PO Box 54224, Masdar City, Abu Dhabi, United Arab Emirates
| | - Jakub Szlachetko
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
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10
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Tang M, Zhang Y, Li S, Wu X, Jia Y, Yang G. Mixed-valence Compounds: AuO2
and AuS. Chemphyschem 2018; 19:2989-2994. [DOI: 10.1002/cphc.201800715] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Indexed: 01/31/2023]
Affiliation(s)
- Meng Tang
- Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education; National Demonstration Center for Experimental Physics Education; Northeast Normal University; Changchun 130024 China
| | - Yanmei Zhang
- Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education; National Demonstration Center for Experimental Physics Education; Northeast Normal University; Changchun 130024 China
| | - Siya Li
- Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education; National Demonstration Center for Experimental Physics Education; Northeast Normal University; Changchun 130024 China
| | - Xi Wu
- Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education; National Demonstration Center for Experimental Physics Education; Northeast Normal University; Changchun 130024 China
| | - Yan Jia
- Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education; National Demonstration Center for Experimental Physics Education; Northeast Normal University; Changchun 130024 China
| | - Guochun Yang
- Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education; National Demonstration Center for Experimental Physics Education; Northeast Normal University; Changchun 130024 China
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11
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Revealing hole trapping in zinc oxide nanoparticles by time-resolved X-ray spectroscopy. Nat Commun 2018; 9:478. [PMID: 29396396 PMCID: PMC5797134 DOI: 10.1038/s41467-018-02870-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 01/05/2018] [Indexed: 12/02/2022] Open
Abstract
Nanostructures of transition metal oxides, such as zinc oxide, have attracted considerable interest for solar-energy conversion and photocatalysis. Both applications are sensitive to the transport and trapping of photoexcited charge carriers. The probing of electron trapping has recently become possible using time-resolved element-sensitive methods, such as X-ray spectroscopy. However, valence-band-trapped holes have so far escaped observation. Herein we use X-ray absorption spectroscopy combined with a dispersive X-ray emission spectrometer to probe the charge carrier relaxation and trapping processes in zinc oxide nanoparticles after above band-gap photoexcitation. Our results, supported by simulations, demonstrate that within 80 ps, photoexcited holes are trapped at singly charged oxygen vacancies, which causes an outward displacement by ~15% of the four surrounding zinc atoms away from the doubly charged vacancy. This identification of the hole traps provides insight for future developments of transition metal oxide-based nanodevices. Metal-oxide nanostructures are used in a range of light-driven applications, yet the fundamentals behind their properties are poorly understood. Here the authors probe photoexcited zinc oxide nanoparticles using time-resolved X-ray spectroscopy, identifying photocatalytically-active hole traps as oxygen vacancies in the lattice.
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12
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Pichler M, Szlachetko J, Castelli IE, Marzari N, Döbeli M, Wokaun A, Pergolesi D, Lippert T. Determination of Conduction and Valence Band Electronic Structure of LaTiO x N y Thin Film. CHEMSUSCHEM 2017; 10:2099-2106. [PMID: 28332773 DOI: 10.1002/cssc.201601632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/13/2017] [Indexed: 06/06/2023]
Abstract
The nitrogen substitution into the oxygen sites of several oxide materials leads to a reduction of the band gap to the visible-light energy range, which makes these oxynitride semiconductors potential photocatalysts for efficient solar water splitting. Oxynitrides typically show a different crystal structure compared to the pristine oxide material. As the band gap is correlated to both the chemical composition and the crystal structure, it is not trivial to distinguish which modifications of the electronic structure induced by the nitrogen substitution are related to compositional and/or structural effects. Here, X-ray emission and absorption spectroscopy are used to investigate the electronic structures of orthorhombic perovskite LaTiOx Ny thin films in comparison with films of the pristine oxide LaTiOx with similar orthorhombic structure and cationic oxidation state. Experiment and theory show the expected upward shift in energy of the valence band maximum that reduces the band gap as a consequence of the nitrogen incorporation. This study also shows that the conduction band minimum, typically considered almost unaffected by nitrogen substitution, undergoes a significant downward shift in energy. For a rational design of oxynitride photocatalysts, the observed changes of both the unoccupied and occupied electronic states have to be taken into account to justify the total band-gap narrowing induced by the nitrogen incorporation.
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Affiliation(s)
- Markus Pichler
- Research with Neutrons and Muons Division, Paul Scherrer Institut, 5232, Villigen-PSI, Switzerland
| | - Jakub Szlachetko
- Paul Scherrer Institut, 5232, Villigen-PSI, Switzerland
- Institute of Physics, Jan Kochanowski University, Kielce, Poland
| | - Ivano E Castelli
- Theory and Simulation of Materials and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland
| | - Nicola Marzari
- Theory and Simulation of Materials and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland
| | - Max Döbeli
- Ion Beam Physics, ETH Zurich, 8093, Zurich, Switzerland
| | - Alexander Wokaun
- Research with Neutrons and Muons Division, Paul Scherrer Institut, 5232, Villigen-PSI, Switzerland
| | - Daniele Pergolesi
- Research with Neutrons and Muons Division, Paul Scherrer Institut, 5232, Villigen-PSI, Switzerland
| | - Thomas Lippert
- Research with Neutrons and Muons Division, Paul Scherrer Institut, 5232, Villigen-PSI, Switzerland
- Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093, Zurich, Switzerland
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13
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A Practical Guide to High-resolution X-ray Spectroscopic Measurements and their Applications in Bioinorganic Chemistry. Isr J Chem 2016. [DOI: 10.1002/ijch.201600037] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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14
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Berger G, Fusaro L, Luhmer M, Czapla-Masztafiak J, Lipiec E, Szlachetko J, Kayser Y, Fernandes DLA, Sá J, Dufrasne F, Bombard S. Insights into the structure–activity relationships of chiral 1,2-diaminophenylalkane platinum(II) anticancer derivatives. J Biol Inorg Chem 2015; 20:841-53. [DOI: 10.1007/s00775-015-1270-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 05/03/2015] [Indexed: 01/28/2023]
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15
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Staniuk M, Zindel D, van Beek W, Hirsch O, Kränzlin N, Niederberger M, Koziej D. Matching the organic and inorganic counterparts during nucleation and growth of copper-based nanoparticles – in situ spectroscopic studies. CrystEngComm 2015. [DOI: 10.1039/c5ce00454c] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Closing the loop: initially, the reactivity of benzyl alcohol determines the nucleation of Cu nanoparticles, but as soon as they start to form they begin to catalyze the condensation of benzyl alcohol to dibenzylether.
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Affiliation(s)
- Malwina Staniuk
- Laboratory for Multifunctional Materials
- Department of Materials
- ETH Zurich
- 8093 Zurich, Switzerland
| | - Daniel Zindel
- Laboratory of Physical Chemistry
- ETH Zurich
- 8093 Zurich, Switzerland
| | - Wouter van Beek
- Swiss-Norwegian Beamlines at European Synchrotron Research Facility
- 38043 Grenoble, France
| | - Ofer Hirsch
- Laboratory for Multifunctional Materials
- Department of Materials
- ETH Zurich
- 8093 Zurich, Switzerland
| | - Niklaus Kränzlin
- Laboratory for Multifunctional Materials
- Department of Materials
- ETH Zurich
- 8093 Zurich, Switzerland
| | - Markus Niederberger
- Laboratory for Multifunctional Materials
- Department of Materials
- ETH Zurich
- 8093 Zurich, Switzerland
| | - Dorota Koziej
- Laboratory for Multifunctional Materials
- Department of Materials
- ETH Zurich
- 8093 Zurich, Switzerland
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16
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Błachucki W, Szlachetko J, Hoszowska J, Dousse JC, Kayser Y, Nachtegaal M, Sá J. High energy resolution off-resonant spectroscopy for x-ray absorption spectra free of self-absorption effects. PHYSICAL REVIEW LETTERS 2014; 112:173003. [PMID: 24836243 DOI: 10.1103/physrevlett.112.173003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Indexed: 06/03/2023]
Abstract
X-ray emission spectra recorded in the off-resonant regime carry information on the density of unoccupied states. It is known that by employing the Kramers-Heisenberg formalism, the high energy resolution off-resonant spectroscopy (HEROS) is equivalent to the x-ray absorption spectroscopy (XAS) technique and provides the same electronic state information. Moreover, in the present Letter we demonstrate that the shape of HEROS spectra is not modified by self-absorption effects. Therefore, in contrast to the fluorescence-based XAS techniques, the recorded shape of the spectra is independent of the sample concentration or thickness. The HEROS may thus be used as an experimental technique when precise information about specific absorption features and their strengths is crucial for chemical speciation or theoretical evaluation.
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Affiliation(s)
- W Błachucki
- Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - J Szlachetko
- Paul Scherrer Institute, CH-5232 Villigen-PSI, Switzerland and Institute of Physics, Jan Kochanowski University, 25-406 Kielce, Poland
| | - J Hoszowska
- Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - J-Cl Dousse
- Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - Y Kayser
- Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - M Nachtegaal
- Paul Scherrer Institute, CH-5232 Villigen-PSI, Switzerland
| | - J Sá
- Paul Scherrer Institute, CH-5232 Villigen-PSI, Switzerland
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17
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Lipiec E, Czapla J, Szlachetko J, Kayser Y, Kwiatek W, Wood B, Deacon GB, Sá J. Novel in situ methodology to observe the interactions of chemotherapeutical Pt drugs with DNA under physiological conditions. Dalton Trans 2014; 43:13839-44. [DOI: 10.1039/c4dt00861h] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The binding of the antitumor drug cisplatin with DNA was determined by means of in situ resonant inelastic X-ray scattering (RIXS) spectroscopy.
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Affiliation(s)
- Ewelina Lipiec
- The Henryk Niewodniczanski Institute of Nuclear Physics
- 31-342 Kraków, Poland
| | - Joanna Czapla
- The Henryk Niewodniczanski Institute of Nuclear Physics
- 31-342 Kraków, Poland
| | - Jakub Szlachetko
- Paul Scherrer Institute (PSI)
- 5232 Villigen, Switzerland
- Institute of Physics
- Jan Kochanowski University in Kielce
- 25-406 Kielce, Poland
| | - Yves Kayser
- Paul Scherrer Institute (PSI)
- 5232 Villigen, Switzerland
| | - Wojciech Kwiatek
- The Henryk Niewodniczanski Institute of Nuclear Physics
- 31-342 Kraków, Poland
| | - Bayden Wood
- Centre for Biospectroscopy
- School of Chemistry
- Monash University
- Victoria, Australia
| | - Glen B. Deacon
- School of Chemistry
- Faculty of Science
- Monash University
- Victoria, Australia
| | - Jacinto Sá
- Paul Scherrer Institute (PSI)
- 5232 Villigen, Switzerland
- Institute of Physical Chemistry
- Polish Academy of Sciences
- Warsaw, Poland
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