Project

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Near ambient pressure photoelectron spectroscopy for environmental and catalysis research

Applicant Ammann Markus
Number 139139
Funding scheme R'EQUIP
Research institution Paul Scherrer Institut
Institution of higher education Paul Scherrer Institute - PSI
Main discipline Physical Chemistry
Start/End 01.12.2011 - 31.12.2013
Approved amount 550'000.00
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All Disciplines (4)

Discipline
Physical Chemistry
Chemical Engineering
Condensed Matter Physics
Climatology. Atmospherical Chemistry, Aeronomy

Keywords (5)

X-ray photoelectron spectroscopy; surface chemistry; Aerosol; Catalysis; synchrotron

Lay Summary (English)

Lead
Lay summary

X-ray photoelectron spectroscopy (XPS) performed at pressures up to 20 mbar (here referred to as near-ambient pressure photoemission, NAPP) is an emerging tool that allows probing the chemistry of surfaces that are relevant to catalysis and the environment under nearly realistic reactant and pressure conditions, thus largely overcoming the pressure gap that separates the basic UHV-based surface science technique and the conditions of real applications.

NAPP at PSI will push the molecular level surface chemistry on particles, ice and other environmental surfaces, which are relevant to understanding atmospheric composition change and to assessing the impact of human activities on climate change. The second target research field is catalysis. Understanding how a catalyst functions, through the development of structure-performance relations, enables improving existing processes and, ultimately, the design of new better ones. These developments are required to produce energy and chemicals in a sustainable manner in the nearest future.

The basic concept of NAPP is that the sample is exposed to a gas or liquid environment and that the photoelectrons are sampled through a differentially pumped electrostatic lens system into an electron energy analyzer held at UHV. Only a handful of further synchrotron-based or lab X-ray source based instruments exist worldwide. The instrument set up at PSI will be at the forefront of the current development regarding energy and pressure range as well as the definition of the sample environment.

We will set up a NAPP instrument as a mobile end station prepared for beam lines of the Swiss Light Source (SLS). For environmental surface chemistry, the long-term focus is establishing a molecular level description of the climate and air pollution impact of atmospheric particles. This requires in situ photoemission experiments with solid materials at high water vapour pressure, on aqueous solution droplet trains and submicron particle beams to allow kinetic and photochemical experiments. The latter configurations circumvent major obstacles related to beam damage of radiation sensitive environmental materials. In the field of catalysis, the ultimate aim is to measure industrially relevant catalyst structures under catalytic conditions that have realistic flow dynamics.

Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Publications

Publication
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
Brown Matthew A., Redondo Amaia Beloqui, Jordan Inga, Duyckaerts Nicolas, Lee Ming-Tao, Ammann Markus, Nolting Frithjof, Kleibert Armin, Huthwelker Thomas, Machler Jean-Pierre, Birrer Mario, Honegger Juri, Wetter Reto, Wörner Hans Jakob, van Bokhoven Jeroen A. (2013), 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, in Review of Scientific Instruments, 84(7), 073904-8-8.
Effect of Surface Charge Density on the Affinity of Oxide Nanoparticles for the Vapor-Water Interface
Brown Matthew A., Duyckaerts Nicolas, Beloqui Redondo Amaia, Jordan Inga, Nolting Frithjof, Keibert Armin, Ammann Markus, Woerner Hans Jakob, van Bokhoven Jeroen A., Abbas Zareen (2013), Effect of Surface Charge Density on the Affinity of Oxide Nanoparticles for the Vapor-Water Interface, in LANGMUIR, 29(16), 5023-5029.
In situ photoelectron spectroscopy at the liquid/nanoparticle interface
Brown Matthew A., Jordan Inga, Beloqui Redondo Amaia, Kleibert Armin, Woerner Hans Jakob, van Bokhoven Jeroen A. (2013), In situ photoelectron spectroscopy at the liquid/nanoparticle interface, in SURFACE SCIENCE, 610, 1-6.

Collaboration

Group / person Country
Types of collaboration
J. Schnaadt, MAX IV Laboratory Sweden (Europe)
- in-depth/constructive exchanges on approaches, methods or results
H. Bluhm, Advanced Light Source, Lawrence Berkeley National Laboratory United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
T. Huthwelker & M. Janousch/SLS Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
Prof. Dr. Majed Chergui / EPFL Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Frithjof Nolting, Swiss Light Source, Paul Scherrer Institut Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
O. Kröcher/PSI Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Exchange of personnel

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
MAX IV User Meeting Talk given at a conference Observing atmospheric processes in aerosol particles and ice - a STXM and XPS perspective 23.09.2013 Lund, Sweden Ammann Markus;
Davos Atmosphere and Cryosphere Assembly 2013 Talk given at a conference Effects of Adsorbates on the hydrogen bonding environment at the surface of ice and frozen solutions 08.07.2013 Davos, Switzerland Ammann Markus;
Gorden Research Conferences "Hydrogen-Metal Systems" Talk given at a conference Near ambient pressure hard X-ray photoelectron spectroscopy 04.07.2013 Barga, Luca, Italy van Bokhoven Jeroen Anton; Ammann Markus;
European Geophysical Union General Assembly 2013 Poster Competition at solution - air interfaces between bromide and citric acid via coated wall flow tube experiments and liquid-jet XPS 07.04.2013 Vienna, Austria Ammann Markus; Brown Matthew;
245th American Chemical Society National Meeting Talk given at a conference Structure of formic acid in the liquid phase at the vapor/liquid interface 07.04.2013 New Orleans, United States of America Brown Matthew; van Bokhoven Jeroen Anton; Ammann Markus;


Associated projects

Number Title Start Funding scheme
121857 The uptake of peroxynitric acid on ice surfaces: The role of grain boundaries and of dissociation 01.06.2009 Project funding (Div. I-III)
125179 Structure-chemistry interaction during snow metamorphism 01.05.2009 Project funding (Div. I-III)
153578 Surface Chemistry at the Water-Oxide Nanoparticle Interface 01.12.2014 Project funding (Div. I-III)
149492 The surface chemistry of tropospheric gas - particle interactions 01.12.2013 Project funding (Div. I-III)
162320 Poisson-Helmholtz-Boltzmann Model Development for Application to Electrical Double Layer Structure Determination 01.05.2015 International short research visits
149629 Surface Sensitive Investigations of the Interaction of Atmospheric Acidic Trace Gases with Ice Surfaces 01.03.2014 Project funding (Div. I-III)
124458 Elucidation of the reaction mechanism of chemo-selective hydrogenation of substituted nitrobenzenes over supported gold catalysts 01.11.2009 Project funding (Div. I-III)
130175 Heterogeneous chemistry of tropospheric aerosol particles with nitrogen oxides from trace gas kinetics, surface chemical and bulk structural perspectives 01.09.2010 Project funding (Div. I-III)

Abstract

X-ray photoelectron spectroscopy (XPS) performed at pressures up to 20 mbar (here referred to as near-ambient pressure photoemission, NAPP) is an emerging tool that allows probing the chemistry of surfaces that are relevant to catalysis and the environment under nearly realistic reactant and pressure conditions, thus largely overcoming the pressure gap that separates the basic UHV-based surface science technique and the conditions of real applications.NAPP at PSI will push the molecular level surface chemistry on particles, ice and other environmental surfaces, which are relevant to understanding atmospheric composition change and to assessing the impact of human activities on climate change. The second target research field is catalysis. Understanding how a catalyst functions, through the development of structure-performance relations, enables improving existing processes and, ultimately, the design of new better ones. These developments are required to produce energy and chemicals in a sustainable manner in the nearest future.The basic concept of NAPP is that the sample is exposed to a gas or liquid environment and that the photo-electrons are sampled through a differentially pumped electrostatic lens system into an electron energy analyzer held at UHV. Scattering of the electrons by the gas phase molecules and the pressure field distor-tion around the sampling aperture into the lower pressure lens system provides constraints on the maximum pressures attainable. The only synchrotron user facilities holding a high pressure XPS end station are highly oversubscribed beamlines at the Advanced Light Source (ALS). Only a handful of further synchrotron-based or lab X-ray source based instruments exist worldwide.We propose to set up a NAPP instrument as a mobile end station prepared for the SIM and PHOENIX beam lines of the Swiss Light Source. We intend to use the instrumentation to solve scientific questions that are relevant to catalysis and energy conversion and the environment. For environmental surface chemistry, the long-term focus is establishing a molecular level description of the climate and air pollution impact of atmospheric particles. This requires in situ photoemission experiments with solid materials at high water vapour pressure, on aqueous solution droplet trains and submicron particle beams to allow kinetic and photochemical experiments. The latter configurations circumvent major obstacles related to beam damage of radiation sensitive environmental materials. In the field of catalysis, the ultimate aim is to measure industrially relevant catalyst structures under catalytic conditions that have realistic flow dynamics. The high photon flux available at the SIM beam line is of paramount importance for measuring nano-particle beams, droplet trains, and catalysts with low content of active component while the broad energy range of the PHOENIX beamline provides unique opportunities for studies that require higher incident energies.The differentially pumped electrostatic lens system, which allows high transmission to a traditional electron kinetic energy analyzer is commercially available. The first innovation of our proposal lies in expanding the photoelectron kinetic energy to 7 keV to better compare surface vs. bulk composition and to get a handle on buried solid/liquid interfaces. The second innovative aspect is the sample environments we are envisioning. While other instruments under development at different synchrotron facilities, such as ALS, ALBA or Brookhaven, concentrate on analyzing samples both under UHV and elevated pressure using the same configuration, we propose to design experimental chambers that accommodate novel sample environments such as liquid jets and catalytic flow reactors. On the long-term, as a most significant innovation, we will develop experiments for NAPP on free nanoparticle beams. The development of a liquid jet or a controlled train of nanoparticles of solid or soft matter will allow timed experiments. This opens the path to fast kinet-ics experiments, such as pump-probe and other configurations.
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