1
|
Pugini M, Credidio B, Walter I, Malerz S, Trinter F, Stemer D, Hergenhahn U, Meijer G, Wilkinson I, Winter B, Thürmer S. How to measure work functions from aqueous solutions. Chem Sci 2023; 14:9574-9588. [PMID: 37712029 PMCID: PMC10498509 DOI: 10.1039/d3sc01740k] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 07/28/2023] [Indexed: 09/16/2023] Open
Abstract
The recent application of concepts from condensed-matter physics to photoelectron spectroscopy (PES) of volatile, liquid-phase systems has enabled the measurement of electronic energetics of liquids on an absolute scale. Particularly, vertical ionization energies, VIEs, of liquid water and aqueous solutions, both in the bulk and at associated interfaces, can now be accurately, precisely, and routinely determined. These IEs are referenced to the local vacuum level, which is the appropriate quantity for condensed matter with associated surfaces, including liquids. In this work, we connect this newly accessible energy level to another important surface property, namely, the solution work function, eΦliq. We lay out the prerequisites for and unique challenges of determining eΦ of aqueous solutions and liquids in general. We demonstrate - for a model aqueous solution with a tetra-n-butylammonium iodide (TBAI) surfactant solute - that concentration-dependent work functions, associated with the surface dipoles generated by the segregated interfacial layer of TBA+ and I- ions, can be accurately measured under controlled conditions. We detail the nature of surface potentials, uniquely tied to the nature of the flowing-liquid sample, which must be eliminated or quantified to enable such measurements. This allows us to refer aqueous-phase spectra to the Fermi level and to quantitatively assign surfactant-concentration-dependent spectral shifts to competing work function and electronic-structure effects, where the latter are typically associated with solute-solvent interactions in the bulk of the solution which determine, e.g., chemical reactivity. The present work describes the extension of liquid-jet PES to quantitatively access concentration-dependent surface descriptors that have so far been restricted to solid-phase measurements. Correspondingly, these studies mark the beginning of a new era in the characterization of the interfacial electronic structure of aqueous solutions and liquids more generally.
Collapse
Affiliation(s)
- Michele Pugini
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Bruno Credidio
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Irina Walter
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Sebastian Malerz
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Florian Trinter
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
- Institut für Kernphysik, Goethe-Universität Max-von-Laue-Straße 1 60438 Frankfurt am Main Germany
| | - Dominik Stemer
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Uwe Hergenhahn
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Gerard Meijer
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Iain Wilkinson
- Institute for Electronic Structure Dynamics, Helmholtz-Zentrum Berlin für Materialien und Energie Hahn-Meitner-Platz 1 14109 Berlin Germany
| | - Bernd Winter
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6 14195 Berlin Germany
| | - Stephan Thürmer
- Department of Chemistry, Graduate School of Science, Kyoto University Kitashirakawa-Oiwakecho, Sakyo-Ku 606-8502 Kyoto Japan
| |
Collapse
|
2
|
Ciocarlan RG, Blommaerts N, Lenaerts S, Cool P, Verbruggen SW. Recent Trends in Plasmon-Assisted Photocatalytic CO 2 Reduction. CHEMSUSCHEM 2023; 16:e202201647. [PMID: 36626298 DOI: 10.1002/cssc.202201647] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 01/10/2023] [Indexed: 06/17/2023]
Abstract
Direct photocatalytic reduction of CO2 has become an highly active field of research. It is thus of utmost importance to maintain an overview of the various materials used to sustain this process, find common trends, and, in this way, eventually improve the current conversions and selectivities. In particular, CO2 photoreduction using plasmonic photocatalysts under solar light has gained tremendous attention, and a wide variety of materials has been developed to reduce CO2 towards more practical gases or liquid fuels (CH4 , CO, CH3 OH/CH3 CH2 OH) in this manner. This Review therefore aims at providing insights in current developments of photocatalysts consisting of only plasmonic nanoparticles and semiconductor materials. By classifying recent studies based on product selectivity, this Review aims to unravel common trends that can provide effective information on ways to improve the photoreduction yield or possible means to shift the selectivity towards desired products, thus generating new ideas for the way forward.
Collapse
Affiliation(s)
- Radu-George Ciocarlan
- Department of Chemistry, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium
| | - Natan Blommaerts
- Department of Chemistry, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium
- Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
| | - Silvia Lenaerts
- Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
| | - Pegie Cool
- Department of Chemistry, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium
| | - Sammy W Verbruggen
- Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
| |
Collapse
|
3
|
Ammann M, Artiglia L. Solvation, Surface Propensity, and Chemical Reactions of Solutes at Atmospheric Liquid-Vapor Interfaces. Acc Chem Res 2022; 55:3641-3651. [PMID: 36472357 PMCID: PMC9774673 DOI: 10.1021/acs.accounts.2c00604] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
surface is covered by oceans, a large number of liquid aerosol particles fill the air, and clouds hold a tiny but critical fraction of Earth's water in the air to influence our climate and hydrology, enabling the lives of humans and ecosystems. The surfaces of these liquids provide the interface for the transfer of gases, for nucleation processes, and for catalyzing important chemical reactions. Coupling a range of spectroscopic tools to liquid microjets has become an important approach to better understanding dynamics, structure, and chemistry at liquid interfaces. Liquid microjets offer stability in vacuum and ambient pressure environments, thus also allowing X-ray photoelectron spectroscopy (XPS) with manageable efforts in terms of differential pumping. Liquid microjets are operated at speeds sufficient to allow for a locally equilibrated surface in terms of water dynamics and solute surface partitioning. XPS is based on the emission of core-level electrons, the binding energy of which is selective for the element and its chemical environment. Inelastic scattering of electrons establishes the probing depth of XPS in the nanometer range and thus its surface sensitivity.In this Account, we focus on aqueous solutions relevant to the surface of oceans, aqueous aerosols, or cloudwater. We are interested in understanding solvation and acid dissociation at the interface, interfacial aspects of reactions with gas-phase reactants, and the interplay of ions with organic molecules at the interface. The strategy is to obtain a link between the molecular-level picture and macroscopic properties and reactivity in the atmospheric context.We show consistency between surface tension and XPS for a range of surface-active organic species as an important proof for interrogating an equilibrated liquid surface. Measurements with organic acids and amines offer important insight into the question of apparent acidity or basicity at the interface. Liquid microjet XPS has settled the debate of the surface enhancement of halide ions, shown using the example of bromide and its oxidation products. Despite the absence of a strong enhancement for the bromide ion, its rate of oxidation by ozone is surface catalyzed through the stabilization of the bromide ozonide intermediate at the interface. In another reaction system, the one between Fe2+ and H2O2, a similar intermediate in the form of highly valent iron species could not be detected by XPS under the experimental conditions employed, shedding light on the abundance of this intermediate in the environment but also on the constraints within which surface species can be detected. Emphasizing the importance of electrostatic effects, we show how a cationic surfactant attracts charged bromide anions to the interface, accompanied by enhanced oxidation rates by ozone, overriding the role of surfactants as a barrier for the access of gas-phase reactants. The reactivity and structure at interfaces thus result from a subtle balance between hygroscopic and hydrophobic interactions, electrostatic effects, and the structural properties of both liquids and solutes.
Collapse
|
4
|
Rashid MH, Borca CN, Xto JM, Huthwelker T. X-Ray absorption spectroscopy on airborne aerosols. ENVIRONMENTAL SCIENCE: ATMOSPHERES 2022; 2:1338-1350. [PMID: 36561554 PMCID: PMC9648630 DOI: 10.1039/d2ea00016d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 09/26/2022] [Indexed: 11/07/2022]
Abstract
Here we demonstrate a method for performing X-ray absorption spectroscopy (XAS) on airborne aerosols. XAS provides unique insight into elemental composition, chemical and phase state, local coordination and electronic structure of both crystalline and amorphous matter. The aerosol is generated from different salt solutions using a commercial atomizer and dried using a diffusion drier. Embedded in a carrier gas, the aerosol is guided into the experimental chamber for XAS analysis. Typical particle sizes range from some 10 to a few 100 nm. Inside the chamber the aerosol bearing gas is then confined into a region of about 1-2 cm3 in size, by a pure flow of helium, generating a stable free-flowing stream of aerosol. It is hit by a monochromatic X-ray beam, and the emitted fluorescent light is used for spectroscopic analysis. Using an aerosol generated from CaCl2, KCl, and (NH4)2SO4 salt solutions, we demonstrate the functionality of the system in studying environmentally relevant systems. In addition, we show that the detection limits are sufficient to also observe subtle spectroscopic signatures in XAS spectra with integration times of about 1-2 hours using a bright undulator beamline. This novel setup opens new research opportunities for studying the nucleation of new phases in multicomponent aerosol systems in situ, and for investigating (photo-) chemical reactions on airborne matter, as relevant to both atmospheric science and also for general chemical application.
Collapse
Affiliation(s)
- Muhammad H. Rashid
- Paul Scherrer Institute, Swiss Light Source, Laboratory for FemtochemistryForschungsstrasse 111Villigen PSISwitzerland
| | - Camelia N. Borca
- Paul Scherrer Institute, Swiss Light Source, Laboratory for FemtochemistryForschungsstrasse 111Villigen PSISwitzerland
| | - Jacinta M. Xto
- Paul Scherrer Institute, Swiss Light Source, Laboratory for FemtochemistryForschungsstrasse 111Villigen PSISwitzerland
| | - Thomas Huthwelker
- Paul Scherrer Institute, Swiss Light Source, Laboratory for FemtochemistryForschungsstrasse 111Villigen PSISwitzerland
| |
Collapse
|
5
|
Ionic distribution of MgCl2 near the alcohol/water interface. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
6
|
Diveky ME, Gleichweit MJ, Roy S, Signorell R. Shining New Light on the Kinetics of Water Uptake by Organic Aerosol Particles. J Phys Chem A 2021; 125:3528-3548. [PMID: 33739837 DOI: 10.1021/acs.jpca.1c00202] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The uptake of water vapor by various organic aerosols is important in a number of applications ranging from medical delivery of pharmaceutical aerosols to cloud formation in the atmosphere. The coefficient that describes the probability that the impinging gas-phase molecule sticks to the surface of interest is called the mass accommodation coefficient, αM. Despite the importance of this coefficient for the description of water uptake kinetics, accurate values are still lacking for many systems. In this Feature Article, we present various experimental techniques that have been evoked in the literature to study the interfacial transport of water and discuss the corresponding strengths and limitations. This includes our recently developed technique called photothermal single-particle spectroscopy (PSPS). The PSPS technique allows for a retrieval of αM values from three independent, yet simultaneous measurements operating close to equilibrium, providing a robust assessment of interfacial mass transport. We review the currently available data for αM for water on various organics and discuss the few studies that address the temperature and relative humidity dependence of αM for water on organics. The knowledge of the latter, for example, is crucial to assess the water uptake kinetics of organic aerosols in the Earth's atmosphere. Finally, we argue that PSPS might also be a viable method to better restrict the αM value for water on liquid water.
Collapse
Affiliation(s)
- Matus E Diveky
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Michael J Gleichweit
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Sandra Roy
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Ruth Signorell
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| |
Collapse
|
7
|
Dupuy R, Richter C, Winter B, Meijer G, Schlögl R, Bluhm H. Core level photoelectron spectroscopy of heterogeneous reactions at liquid-vapor interfaces: Current status, challenges, and prospects. J Chem Phys 2021; 154:060901. [PMID: 33588531 DOI: 10.1063/5.0036178] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Liquid-vapor interfaces, particularly those between aqueous solutions and air, drive numerous important chemical and physical processes in the atmosphere and in the environment. X-ray photoelectron spectroscopy is an excellent method for the investigation of these interfaces due to its surface sensitivity, elemental and chemical specificity, and the possibility to obtain information on the depth distribution of solute and solvent species in the interfacial region. In this Perspective, we review the progress that was made in this field over the past decades and discuss the challenges that need to be overcome for investigations of heterogeneous reactions at liquid-vapor interfaces under close-to-realistic environmental conditions. We close with an outlook on where some of the most exciting and promising developments might lie in this field.
Collapse
Affiliation(s)
- Rémi Dupuy
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Clemens Richter
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Bernd Winter
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Gerard Meijer
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Robert Schlögl
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Hendrik Bluhm
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, D-14195 Berlin, Germany
| |
Collapse
|
8
|
Guo H, Yulaev A, Strelcov E, Tselev A, Arble C, Vladar AE, Villarrubia JS, Kolmakov A. Probing Electrified Liquid-Solid Interfaces with Scanning Electron Microscopy. ACS APPLIED MATERIALS & INTERFACES 2020; 12:56650-56657. [PMID: 33327058 DOI: 10.1021/acsami.0c19634] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Electrical double layers play a key role in a variety of electrochemical systems. The mean free path of secondary electrons in aqueous solutions is on the order of a nanometer, making them suitable for probing ultrathin electrical double layers at solid-liquid electrolyte interfaces. Employing graphene as an electron-transparent electrode in a two-electrode electrochemical system, we show that the secondary electron yield of the graphene-liquid interface depends on the ionic strength and concentration of the electrolyte and the applied bias at the remote counter electrode. These observations have been related to polarization-induced changes in the potential distribution within the electrical double layer and demonstrate the feasibility of using scanning electron microscopy to examine and map electrified liquid-solid interfaces.
Collapse
Affiliation(s)
- Hongxuan Guo
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 210096, P. R. China
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
- Maryland Nanocenter, University of Maryland, College Park, Maryland 20742, United States
| | - Alexander Yulaev
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
- Maryland Nanocenter, University of Maryland, College Park, Maryland 20742, United States
| | - Evgheni Strelcov
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
- Maryland Nanocenter, University of Maryland, College Park, Maryland 20742, United States
| | - Alexander Tselev
- Department of Physics and CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro 3810-193, Portugal
| | - Christopher Arble
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Andras E Vladar
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - John S Villarrubia
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Andrei Kolmakov
- Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| |
Collapse
|
9
|
Abstract
Intriguing properties of photoemission from free, unsupported particles and droplets were predicted nearly 50 years ago, though experiments were a technical challenge. The last few decades have seen a surge of research in the field, due to advances in aerosol technology (generation, characterization, and transfer into vacuum), the development of photoelectron imaging spectrometers, and advances in vacuum ultraviolet and ultrafast light sources. Particles and droplets offer several advantages for photoemission studies. For example, photoemission spectra are dependent on the particle's size, shape, and composition, providing a wealth of information that allows for the retrieval of genuine electronic properties of condensed phase. In this review, with a focus on submicrometer-sized, dielectric particles and droplets, we explain the utility of photoemission from such systems, summarize several applications from the literature, and present some thoughts on future research directions.
Collapse
Affiliation(s)
- Loren Ban
- Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland;
| | - Bruce L Yoder
- Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland;
| | - Ruth Signorell
- Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland;
| |
Collapse
|
10
|
|
11
|
Collado L, Reynal A, Fresno F, Barawi M, Escudero C, Perez-Dieste V, Coronado JM, Serrano DP, Durrant JR, de la Peña O'Shea VA. Unravelling the effect of charge dynamics at the plasmonic metal/semiconductor interface for CO 2 photoreduction. Nat Commun 2018; 9:4986. [PMID: 30478316 PMCID: PMC6255847 DOI: 10.1038/s41467-018-07397-2] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 10/25/2018] [Indexed: 12/17/2022] Open
Abstract
Sunlight plays a critical role in the development of emerging sustainable energy conversion and storage technologies. Light-induced CO2 reduction by artificial photosynthesis is one of the cornerstones to produce renewable fuels and environmentally friendly chemicals. Interface interactions between plasmonic metal nanoparticles and semiconductors exhibit improved photoactivities under a wide range of the solar spectrum. However, the photo-induced charge transfer processes and their influence on photocatalysis with these materials are still under debate, mainly due to the complexity of the involved routes occurring at different timescales. Here, we use a combination of advanced in situ and time-resolved spectroscopies covering different timescales, combined with theoretical calculations, to unravel the overall mechanism of photocatalytic CO2 reduction by Ag/TiO2 catalysts. Our findings provide evidence of the key factors determining the enhancement of photoactivity under ultraviolet and visible irradiation, which have important implications for the design of solar energy conversion materials.
Collapse
Affiliation(s)
- Laura Collado
- Photoactivated Processes Unit, Institute IMDEA Energy, Avda. Ramón de la Sagra 3, 28935, Madrid, Spain
- Thermochemical Processes Unit, Institute IMDEA Energy, Avda. Ramón de la Sagra 3, 28935, Madrid, Spain
| | - Anna Reynal
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, Exhibition Road, London, SW7 2AZ, United Kingdom
- School of Science, Engineering and Design, Teesside University, Borough Road, Middlesbrough, TS1 3BA, United Kingdom
| | - Fernando Fresno
- Photoactivated Processes Unit, Institute IMDEA Energy, Avda. Ramón de la Sagra 3, 28935, Madrid, Spain
| | - Mariam Barawi
- Photoactivated Processes Unit, Institute IMDEA Energy, Avda. Ramón de la Sagra 3, 28935, Madrid, Spain
| | - Carlos Escudero
- ALBA Synchrotron Light Source, Carretera BP 1413 Km. 3.3, Cerdanyola del Vallès, Spain
| | - Virginia Perez-Dieste
- ALBA Synchrotron Light Source, Carretera BP 1413 Km. 3.3, Cerdanyola del Vallès, Spain
| | - Juan M Coronado
- Thermochemical Processes Unit, Institute IMDEA Energy, Avda. Ramón de la Sagra 3, 28935, Madrid, Spain
| | - David P Serrano
- Thermochemical Processes Unit, Institute IMDEA Energy, Avda. Ramón de la Sagra 3, 28935, Madrid, Spain.
- Department of Chemical and Energy Technology, Rey Juan Carlos University, c/ Tulipán s/n, 28935, Madrid, Spain.
| | - James R Durrant
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, Exhibition Road, London, SW7 2AZ, United Kingdom.
| | | |
Collapse
|
12
|
Rameshan C, Li H, Anic K, Roiaz M, Pramhaas V, Rameshan R, Blume R, Hävecker M, Knudsen J, Knop-Gericke A, Rupprechter G. In situ NAP-XPS spectroscopy during methane dry reforming on ZrO 2/Pt(1 1 1) inverse model catalyst. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:264007. [PMID: 29786619 DOI: 10.1088/1361-648x/aac6ff] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Due to the need of sustainable energy sources, methane dry reforming is a useful reaction for conversion of the greenhouse gases CH4 and CO2 to synthesis gas (CO + H2). Syngas is the basis for a wide range of commodity chemicals and can be utilized for fuel production via Fischer-Tropsch synthesis. The current study focuses on spectroscopic investigations of the surface and reaction properties of a ZrO2/Pt inverse model catalyst, i.e. ZrO2 particles (islands) grown on a Pt(1 1 1) single crystal, with emphasis on in situ near ambient pressure x-ray photoelectron spectroscopy (NAP-XPS) during MDR reaction. In comparison to technological systems, model catalysts facilitate characterization of the surface (oxidation) state, surface adsorbates, and the role of the metal-support interface. Using XPS and infrared reflection absorption spectroscopy we demonstrated that under reducing conditions (UHV or CH4) the ZrO2 particles transformed to an ultrathin ZrO2 film that started to cover (wet) the Pt surface in an SMSI-like fashion, paralleled by a decrease in surface/interface oxygen. In contrast, (more oxidizing) dry reforming conditions with a 1:1 ratio of CH4 and CO2 were stabilizing the ZrO2 particles on the model catalyst surface (or were even reversing the strong metal support interaction (SMSI) effect), as revealed by in situ XPS. Carbon deposits resulting from CH4 dissociation were easily removed by CO2 or by switching to dry reforming conditions (673-873 K). Thus, at these temperatures the active Pt surface remained free of carbon deposits, also preserving the ZrO2/Pt interface.
Collapse
Affiliation(s)
- C Rameshan
- Institute of Materials Chemistry, Technische Universität Wien, Vienna, Austria
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Roy K, Artiglia L, van Bokhoven JA. Ambient Pressure Photoelectron Spectroscopy: Opportunities in Catalysis from Solids to Liquids and Introducing Time Resolution. ChemCatChem 2018. [DOI: 10.1002/cctc.201701522] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Kanak Roy
- Institute for Chemical and Bioengineering; ETH Zürich; Zürich Switzerland
- Laboratory for Catalysis and Sustainable Chemistry; Paul Scherrer Institute; Villigen Switzerland
| | - Luca Artiglia
- Laboratory for Catalysis and Sustainable Chemistry; Paul Scherrer Institute; Villigen Switzerland
| | - Jeroen A. van Bokhoven
- Institute for Chemical and Bioengineering; ETH Zürich; Zürich Switzerland
- Laboratory for Catalysis and Sustainable Chemistry; Paul Scherrer Institute; Villigen Switzerland
| |
Collapse
|
14
|
Bzdek BR, Reid JP. Perspective: Aerosol microphysics: From molecules to the chemical physics of aerosols. J Chem Phys 2017; 147:220901. [DOI: 10.1063/1.5002641] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Bryan R. Bzdek
- School of Chemistry, University of Bristol, Bristol BS8 1TS,
United Kingdom
| | - Jonathan P. Reid
- School of Chemistry, University of Bristol, Bristol BS8 1TS,
United Kingdom
| |
Collapse
|
15
|
Specific cation effects at aqueous solution-vapor interfaces: Surfactant-like behavior of Li + revealed by experiments and simulations. Proc Natl Acad Sci U S A 2017; 114:13363-13368. [PMID: 29078311 DOI: 10.1073/pnas.1707540114] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
It is now well established by numerous experimental and computational studies that the adsorption propensities of inorganic anions conform to the Hofmeister series. The adsorption propensities of inorganic cations, such as the alkali metal cations, have received relatively little attention. Here we use a combination of liquid-jet X-ray photoelectron experiments and molecular dynamics simulations to investigate the behavior of K+ and Li+ ions near the interfaces of their aqueous solutions with halide ions. Both the experiments and the simulations show that Li+ adsorbs to the aqueous solution-vapor interface, while K+ does not. Thus, we provide experimental validation of the "surfactant-like" behavior of Li+ predicted by previous simulation studies. Furthermore, we use our simulations to trace the difference in the adsorption of K+ and Li+ ions to a difference in the resilience of their hydration shells.
Collapse
|
16
|
Kostko O, Xu B, Jacobs MI, Ahmed M. Soft X-ray spectroscopy of nanoparticles by velocity map imaging. J Chem Phys 2017; 147:013931. [DOI: 10.1063/1.4982822] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- O. Kostko
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - B. Xu
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - M. I. Jacobs
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - M. Ahmed
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| |
Collapse
|
17
|
Favaro M, Liu Z, Crumlin EJ. Ambient-Pressure X-ray Photoelectron Spectroscopy to Characterize the Solid/Liquid Interface: Probing the Electrochemical Double Layer. ACTA ACUST UNITED AC 2017. [DOI: 10.1080/08940886.2017.1289806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
18
|
Lin PC, Wu ZH, Chen MS, Li YL, Chen WR, Huang TP, Lee YY, Wang CC. Interfacial Solvation and Surface pH of Phenol and Dihydroxybenzene Aqueous Nanoaerosols Unveiled by Aerosol VUV Photoelectron Spectroscopy. J Phys Chem B 2017; 121:1054-1067. [PMID: 28055205 DOI: 10.1021/acs.jpcb.6b10201] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although the significance of aqueous interfaces has been recognized in numerous important fields, it can be even more prominent for nanoscaled aqueous aerosols because of their large surface-to-volume ratios and prevalent existence in nature. Also, considering that organic species are often mixed with aqueous aerosols in nature, a fundamental understanding of the electronic and structural properties of organic species in aqueous nanoaerosols is essential to learn the interplay between water and organic solutes under the nanoscaled size regime. Here, we report for the first time the vacuum ultraviolet photoelectron spectroscopy of phenol and three dihydroxybenzene (DHB) isomers including catechol, resorcinol, and hydroquinone in the aqueous nanoaerosol form. By evaluating two photoelectron features of the lowest vertical ionization energies originated from the b1(π) and a2(π) orbitals for phenolic aqueous nanoaerosols, their interfacial solvation characteristics are unraveled. Phenolic species appear to reside primarily on/near the aqueous nanoaerosol interface, where they appear only partially hydrated on the aqueous interface with the hydrophilic hydroxyl group more solvated in water. An appreciable proportion of phenol is found to coexist with phenolate at/near the nanoaerosol interface even under a high bulk pH of 12.0, indicating that the nanoaerosol interface exhibits a composition distribution and pH drastically different from those of the bulk. The surface pH of phenol-containing aqueous nanoaerosols is found to be ∼2.2 ± 0.1 units more acidic than that of the bulk interior, as measured at the bulk pH of 12.0. From the photoelectron spectra of DHB aqueous nanoaerosols, the effects of numbers/arrangements of -OH groups are assessed. This study shows that the hydration extents, pH values, deprotonation status, and numbers/relative arrangements of -OH groups are crucial factors affecting the ionization energies of phenolic aqueous nanoaerosols and thus their redox-based activities. The multifaceted implications of the present study in the aerosol science, atmospheric/marine chemistry, and biological science are also addressed.
Collapse
Affiliation(s)
| | | | | | | | | | - Tzu-Ping Huang
- National Synchrotron Radiation Research Center , Hsinchu, Taiwan 30076, ROC
| | - Yin-Yu Lee
- National Synchrotron Radiation Research Center , Hsinchu, Taiwan 30076, ROC
| | | |
Collapse
|
19
|
Trotochaud L, Head AR, Karslıoğlu O, Kyhl L, Bluhm H. Ambient pressure photoelectron spectroscopy: Practical considerations and experimental frontiers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:053002. [PMID: 27911885 DOI: 10.1088/1361-648x/29/5/053002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Over the past several decades, ambient pressure x-ray photoelectron spectroscopy (APXPS) has emerged as a powerful technique for in situ and operando investigations of chemical reactions under relevant ambient atmospheres far from ultra-high vacuum conditions. This review focuses on exemplary cases of APXPS experiments, giving special consideration to experimental techniques, challenges, and limitations specific to distinct condensed matter interfaces. We discuss APXPS experiments on solid/vapor interfaces, including the special case of 2D films of graphene and hexagonal boron nitride on metal substrates with intercalated gas molecules, liquid/vapor interfaces, and liquid/solid interfaces, which are a relatively new class of interfaces being probed by APXPS. We also provide a critical evaluation of the persistent limitations and challenges of APXPS, as well as the current experimental frontiers.
Collapse
Affiliation(s)
- Lena Trotochaud
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | | | | | | | | |
Collapse
|
20
|
Guo H, Strelcov E, Yulaev A, Wang J, Appathurai N, Urquhart S, Vinson J, Sahu S, Zwolak M, Kolmakov A. Enabling Photoemission Electron Microscopy in Liquids via Graphene-Capped Microchannel Arrays. NANO LETTERS 2017; 17:1034-1041. [PMID: 28121153 PMCID: PMC5436695 DOI: 10.1021/acs.nanolett.6b04460] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Photoelectron emission microscopy (PEEM) is a powerful tool to spectroscopically image dynamic surface processes at the nanoscale, but it is traditionally limited to ultrahigh or moderate vacuum conditions. Here, we develop a novel graphene-capped multichannel array sample platform that extends the capabilities of photoelectron spectromicroscopy to routine liquid and atmospheric pressure studies with standard PEEM setups. Using this platform, we show that graphene has only a minor influence on the electronic structure of water in the first few layers and thus will allow for the examination of minimally perturbed aqueous-phase interfacial dynamics. Analogous to microarray screening technology in biomedical research, our platform is highly suitable for applications in tandem with large-scale data mining, pattern recognition, and combinatorial methods for spectro-temporal and spatiotemporal analyses at solid-liquid interfaces. Applying Bayesian linear unmixing algorithm to X-ray induced water radiolysis process, we were able to discriminate between different radiolysis scenarios and observe a metastable "wetting" intermediate water layer during the late stages of bubble formation.
Collapse
Affiliation(s)
- Hongxuan Guo
- Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD 20899
- Maryland NanoCenter, University of Maryland, College Park, MD 20742
| | - Evgheni Strelcov
- Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD 20899
- Maryland NanoCenter, University of Maryland, College Park, MD 20742
| | - Alexander Yulaev
- Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD 20899
- Maryland NanoCenter, University of Maryland, College Park, MD 20742
- Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
| | - Jian Wang
- Canadian Light Source, Saskatoon, SK S7N 2V3, Canada
| | | | - Stephen Urquhart
- Department of Chemistry, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
| | - John Vinson
- Material Measurement Laboratory, NIST, Gaithersburg, MD 20899, USA
| | - Subin Sahu
- Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD 20899
- Maryland NanoCenter, University of Maryland, College Park, MD 20742
- Department of Physics, Oregon State University, OR 97331, USA
| | - Michael Zwolak
- Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD 20899
| | - Andrei Kolmakov
- Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD 20899
| |
Collapse
|
21
|
Ambient-Pressure X-ray Photoelectron Spectroscopy (APXPS). SPRINGER SERIES IN CHEMICAL PHYSICS 2017. [DOI: 10.1007/978-3-319-44439-0_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
22
|
Lee MT, Orlando F, Artiglia L, Chen S, Ammann M. Chemical Composition and Properties of the Liquid–Vapor Interface of Aqueous C1 to C4 Monofunctional Acid and Alcohol Solutions. J Phys Chem A 2016; 120:9749-9758. [DOI: 10.1021/acs.jpca.6b09261] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ming-Tao Lee
- Laboratory
of Environmental Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland
- Department
of Chemistry and Biochemistry, University of Bern, 3012, Bern, Switzerland
| | - Fabrizio Orlando
- Laboratory
of Environmental Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland
| | - Luca Artiglia
- Laboratory
of Environmental Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland
- Laboratory
for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland
| | - Shuzhen Chen
- Laboratory
of Environmental Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland
- Institute
of Atmospheric and Climate Sciences, ETH Zürich, 8092, Zürich, Switzerland
| | - Markus Ammann
- Laboratory
of Environmental Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland
| |
Collapse
|
23
|
Abstract
Ambient-pressure photoelectron spectroscopy (APPES) and microscopy are at the frontier of modern chemical analysis at liquid-gas, solid-liquid and solid-gas interfaces, bridging science and engineering of functional materials. Complementing the current state-of-the art of the instruments, we survey in this short review several alternative APPES approaches, developed recently in the scanning photoelectron microscope (SPEM) at the Elettra laboratory. In particular, we report on experimental setups for dynamic near-ambient pressure environment, using pulsed-gas injection in the vicinity of samples or reaction cells with very small apertures, allowing for experiments without introducing additional differential pumping stages. The major part of the review is dedicated to the construction and performance of novel environmental cells using ultrathin electron-transparent but molecularly impermeable membranes to isolate the gas or liquid ambient from the electron detector operating in ultra-high vacuum (UHV). We demonstrate that two dimensional materials, such as graphene and derivatives, are mechanically robust to withstand atmospheric - UHV pressure differences and are sufficiently transparent for the photoelectrons emitted from samples immersed in the liquid or gaseous media. There are many unique opportunities for APPES using X-rays over a wide energy range. We show representative results that illustrate the potential of these 'ambient-pressure' approaches. Combined with the ca 100 nm lateral resolution of SPEM, they can overcome the pressure gap challenges and address the evolution of chemical composition and electronic structure at surface and interfaces under realistic operation conditions with unprecedented lateral and spectral resolution.
Collapse
|
24
|
Itkis DM, Velasco-Velez JJ, Knop-Gericke A, Vyalikh A, Avdeev MV, Yashina LV. Probing Operating Electrochemical Interfaces by Photons and Neutrons. ChemElectroChem 2015. [DOI: 10.1002/celc.201500155] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Daniil M. Itkis
- Department of Chemistry; Moscow State University; Leninskie gory 1 Moscow 119991 Russia
| | - Juan Jesus Velasco-Velez
- Department of Heterogeneous Reactions, Max Planck Institute for Chemical Energy Conversion; Stiftstrasse 34-36 Mülheim an der Ruhr 45470 Germany
| | - Axel Knop-Gericke
- Department of Inorganic Chemistry, Fritz-Haber-Institut der Max-Planck-Gesellschaft; Faradayweg 4-6 Berlin 1495 Germany
| | - Anastasia Vyalikh
- Institut für Experimentelle Physik; Technische Universität Bergakademie Freiberg; Leipziger Str. 23, EG02 Freiberg 09599 Germany
| | - Mikhail V. Avdeev
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research; Joliot-Curie str. 6 Dubna, Moscow reg. 141980 Russia
| | - Lada V. Yashina
- Department of Inorganic Chemistry; Moscow State University; Leninskie gory 1 Moscow 119991 Russia
| |
Collapse
|
25
|
Seidel R, Atak K, Thürmer S, Aziz EF, Winter B. Ti3+ Aqueous Solution: Hybridization and Electronic Relaxation Probed by State-Dependent Electron Spectroscopy. J Phys Chem B 2015. [DOI: 10.1021/acs.jpcb.5b03337] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Robert Seidel
- Institute
of Methods for Material Development, Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse
15, D-12489 Berlin, Germany
| | - Kaan Atak
- Institute
of Methods for Material Development, Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse
15, D-12489 Berlin, Germany
| | - Stephan Thürmer
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Emad F. Aziz
- Institute
of Methods for Material Development, Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse
15, D-12489 Berlin, Germany
- Department
of Physics, Freie Universität Berlin, Arnimallee 14, D-14159 Berlin, Germany
| | - Bernd Winter
- Institute
of Methods for Material Development, Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse
15, D-12489 Berlin, Germany
| |
Collapse
|
26
|
Su CC, Yu Y, Chang PC, Chen YW, Chen IY, Lee YY, Wang CC. VUV Photoelectron Spectroscopy of Cysteine Aqueous Aerosols: A Microscopic View of Its Nucleophilicity at Varying pH Conditions. J Phys Chem Lett 2015; 6:817-23. [PMID: 26262658 DOI: 10.1021/acs.jpclett.5b00002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Cysteine (Cys) is unique due to its highly reactive thiol group. It often regulates the biological function of proteins by acting as the redox site. Despite its biological significance, however, the valence electronic structure of Cys under the aqueous environments remains unavailable. Here, we report the VUV photoelectron spectroscopy of Cys aqueous aerosols via a newly built aerosol VUV photoelectron spectroscopy apparatus. The photoelectron spectra of Cys show distinct band shapes at varying pH conditions, reflecting the altered molecular orbital characters when its dominating form changes. The ionization energy of Cys is determined to be 8.98 ± 0.05 eV at low pH. A new feature at a binding energy of 6.97 ± 0.05 eV is observed at high pH, suggesting that the negative charge on the thiolate group becomes the first electron to be removed upon ionization. This work implies that when Cys is involved in redox processes, the charge transfer mechanism may be entirely altered under different pH conditions.
Collapse
Affiliation(s)
- Chien-Cheng Su
- †Department of Chemistry, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, Republic of China
| | - Youqing Yu
- †Department of Chemistry, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, Republic of China
| | - Po-Chiao Chang
- †Department of Chemistry, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, Republic of China
| | - Yu-Wei Chen
- †Department of Chemistry, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, Republic of China
| | - I-Ying Chen
- †Department of Chemistry, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, Republic of China
| | - Yin-Yu Lee
- ‡National Synchrotron Radiation Research Center, 30076 Hsinchu, Taiwan, Republic of China
| | - Chia C Wang
- †Department of Chemistry, National Sun Yat-sen University, 80424 Kaohsiung, Taiwan, Republic of China
| |
Collapse
|
27
|
Meyer F, Blum M, Benkert A, Hauschild D, Nagarajan S, Wilks RG, Andersson J, Yang W, Zharnikov M, Bär M, Heske C, Reinert F, Weinhardt L. “Building Block Picture” of the Electronic Structure of Aqueous Cysteine Derived from Resonant Inelastic Soft X-ray Scattering. J Phys Chem B 2014; 118:13142-50. [DOI: 10.1021/jp5089417] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- F. Meyer
- Experimentelle
Physik VII, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - M. Blum
- Department
of Chemistry, University of Nevada, Las Vegas, 4505 Maryland
Parkway, Las Vegas, Nevada 89154-4003, United States
| | - A. Benkert
- Experimentelle
Physik VII, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - D. Hauschild
- Experimentelle
Physik VII, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - S. Nagarajan
- Angewandte
Physikalische Chemie, Universität Heidelberg, INF 253,69120 Heidelberg, Germany
| | - R. G. Wilks
- Solar
Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
| | - J. Andersson
- Department
of Physics and Astronomy, Uppsala University, Box 516, S-751 20 Uppsala, Sweden
| | - W. Yang
- Advanced
Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron
Road, Berkeley, California 94720, United States
| | - M. Zharnikov
- Angewandte
Physikalische Chemie, Universität Heidelberg, INF 253,69120 Heidelberg, Germany
| | - M. Bär
- Department
of Chemistry, University of Nevada, Las Vegas, 4505 Maryland
Parkway, Las Vegas, Nevada 89154-4003, United States
- Solar
Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
- Institut
für Physik und Chemie, Brandenburgische Technische Universität Cottbus-Senftenberg, Platz der Deutschen Einheit 1, 03046 Cottbus, Germany
| | - C. Heske
- Department
of Chemistry, University of Nevada, Las Vegas, 4505 Maryland
Parkway, Las Vegas, Nevada 89154-4003, United States
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstrasse 18/20, 76128 Karlsruhe, Germany
| | - F. Reinert
- Experimentelle
Physik VII, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - L. Weinhardt
- Department
of Chemistry, University of Nevada, Las Vegas, 4505 Maryland
Parkway, Las Vegas, Nevada 89154-4003, United States
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstrasse 18/20, 76128 Karlsruhe, Germany
| |
Collapse
|
28
|
Kraus J, Reichelt R, Günther S, Gregoratti L, Amati M, Kiskinova M, Yulaev A, Vlassiouk I, Kolmakov A. Photoelectron spectroscopy of wet and gaseous samples through graphene membranes. NANOSCALE 2014; 6:14394-403. [PMID: 25333337 DOI: 10.1039/c4nr03561e] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Photoelectron spectroscopy (PES) and microscopy are highly important for exploring morphologically and chemically complex liquid-gas, solid-liquid and solid-gas interfaces under realistic conditions, but the very small electron mean free path inside dense media imposes serious experimental challenges. Currently, near ambient pressure PES is conducted using dexterously designed electron energy analyzers coupled with differentially pumped electron lenses which make it possible to conduct PES measurements at a few hPa. This report proposes an alternative ambient pressure approach that can be applied to a broad class of samples and be implemented in conventional PES instruments. It uses ultrathin electron transparent but molecular impermeable membranes to isolate the high pressure sample environment from the high vacuum PES detection system. We demonstrate that the separating graphene membrane windows are both mechanically robust and sufficiently transparent for electrons in a wide energy range to allow soft X-ray PES of liquid and gaseous water. The performed proof-of-principle experiments confirm the possibility to probe vacuum-incompatible toxic or reactive samples placed inside such hermetic, gas flow or fluidic environmental cells.
Collapse
Affiliation(s)
- Jürgen Kraus
- Technische Universität München, Chemie Department, Lichtenbergstr. 4, D-85748 Garching, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Brown MA, Redondo AB, Jordan I, Duyckaerts N, Lee MT, Ammann M, Nolting F, Kleibert A, Huthwelker T, Müächler JP, Birrer M, Honegger J, Wetter R, Wörner HJ, van Bokhoven JA. A new endstation at the Swiss Light Source for ultraviolet photoelectron spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy measurements of liquid solutions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:073904. [PMID: 23902081 DOI: 10.1063/1.4812786] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A new liquid microjet endstation designed for ultraviolet (UPS) and X-ray (XPS) photoelectron, and partial electron yield X-ray absorption (XAS) spectroscopies at the Swiss Light Source is presented. The new endstation, which is based on a Scienta HiPP-2 R4000 electron spectrometer, is the first liquid microjet endstation capable of operating in vacuum and in ambient pressures up to the equilibrium vapor pressure of liquid water at room temperature. In addition, the Scienta HiPP-2 R4000 energy analyzer of this new endstation allows for XPS measurements up to 7000 eV electron kinetic energy that will enable electronic structure measurements of bulk solutions and buried interfaces from liquid microjet samples. The endstation is designed to operate at the soft X-ray SIM beamline and at the tender X-ray Phoenix beamline. The endstation can also be operated using a Scienta 5 K ultraviolet helium lamp for dedicated UPS measurements at the vapor-liquid interface using either He I or He II α lines. The design concept, first results from UPS, soft X-ray XPS, and partial electron yield XAS measurements, and an outlook to the potential of this endstation are presented.
Collapse
Affiliation(s)
- Matthew A Brown
- Institute for Chemical and Bioengineering, ETH Zürich, CH-8093 Zürich, Switzerland.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Zemlyanov D. Electron spectroscopy: a new window opens. NATURE NANOTECHNOLOGY 2011; 6:612-613. [PMID: 21979233 DOI: 10.1038/nnano.2011.173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
|
31
|
Kolmakov A, Dikin DA, Cote LJ, Huang J, Abyaneh MK, Amati M, Gregoratti L, Günther S, Kiskinova M. Graphene oxide windows for in situ environmental cell photoelectron spectroscopy. NATURE NANOTECHNOLOGY 2011; 6:651-657. [PMID: 21873990 DOI: 10.1038/nnano.2011.130] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 07/14/2011] [Indexed: 05/31/2023]
Abstract
The performance of new materials and devices often depends on processes taking place at the interface between an active solid element and the environment (such as air, water or other fluids). Understanding and controlling such interfacial processes require surface-specific spectroscopic information acquired under real-world operating conditions, which can be challenging because standard approaches such as X-ray photoelectron spectroscopy generally require high-vacuum conditions. The state-of-the-art approach to this problem relies on unique and expensive apparatus including electron analysers coupled with sophisticated differentially pumped lenses. Here, we develop a simple environmental cell with graphene oxide windows that are transparent to low-energy electrons (down to 400 eV), and demonstrate the feasibility of X-ray photoelectron spectroscopy measurements on model samples such as gold nanoparticles and aqueous salt solution placed on the back side of a window. These proof-of-principle results show the potential of using graphene oxide, graphene and other emerging ultrathin membrane windows for the fabrication of low-cost, single-use environmental cells compatible with commercial X-ray and Auger microprobes as well as scanning or transmission electron microscopes.
Collapse
Affiliation(s)
- Andrei Kolmakov
- Southern Illinois University, Carbondale, Illinois 62901, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Valsaraj KT. Trace gas adsorption thermodynamics at the air−water interface: Implications in atmospheric chemistry. PURE APPL CHEM 2009. [DOI: 10.1351/pac-con-08-07-06] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The thermodynamics of adsorption of gaseous organic compounds such as polycyclic aromatic hydrocarbons (PAHs) on water films is reviewed and discussed. The various experimental methods available to determine the thermodynamic equilibrium constant and the structure–activity relationships to correlate and estimate the same are reviewed. The atmospheric implications of the adsorption and oxidation of PAHs at the air–water interface of thin films of water such as existing in fog droplets, ice films, and aerosols are also enumerated.
Collapse
Affiliation(s)
- Kalliat T. Valsaraj
- 1Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
| |
Collapse
|
33
|
Brown MA, Faubel M, Winter B. X-Ray photo- and resonant Auger-electron spectroscopy studies of liquid water and aqueous solutions. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b803023p] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
34
|
Brown MA, D’Auria R, Kuo IFW, Krisch MJ, Starr DE, Bluhm H, Tobias DJ, Hemminger JC. Ion spatial distributions at the liquid–vapor interface of aqueous potassium fluoride solutions. Phys Chem Chem Phys 2008; 10:4778-84. [DOI: 10.1039/b807041e] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|