Current projects in physical and theoretical chemistry
ATMOS
ATMOS is a consortium of 11 research institutions, five of which are based in the EU and manage the project. There are also six partner organizations in third countries. The main objective of the project is to establish cooperation in the investigation of scientific problems of air pollution; in particular, students are to be trained in this area.
14-AMI
The University of Wuppertal is participating in the EU-wide 14AMI project, which focuses on the development of semiconductor chips with a size of 14 Angstroms. EUV lithography with extreme ultraviolet radiation (10-121 nm) is used to expose tiny structures on silicon wafers. The size of the structures directly influences the performance of the chips. The Physical and Theoretical Chemistry department at the University of Wuppertal is dedicated to analyzing the EUV plasma-generated molecules and ions and their interaction with relevant surfaces. To this end, mass spectrometric analysis tools are being developed that are specially designed for the measurement conditions. This contribution is of great importance to improve the understanding of gas-phase and surface reactions in EUV lithography and thus to increase the lifetime of the optics.
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Elucidation of reactant ion dynamics in the High Kinetic Energy Ion Mobility Spectrometer (HiKE-IMS)
In ion mobility spectrometry, ions are separated in an electric field based on their ion mobility.
The High Kinetic Energy Ion Mobility Spectrometer (HiKE-IMS), which was developed by the working group of Prof. Zimmermann (Leibniz Universität Hannover), achieves high electric field strengths in the analyzer area of the instrument and uses a corona discharge as a chemical ion source.
A DFG-funded research project of the working groups of Prof. Benter and Prof. Zimmermann (University of Hanover) characterizes the primary ions resulting from the discharge with a HiKE-IMS coupling to a mass spectrometer (HiKE-IMS-TOF-MS) set up in the first part of the project and investigates the chemical dynamics of this ion ensemble in the HiKE-IMS in detail. In particular, the formation of ion-molecule clusters, such as NO+(H2O)n and O2+(H2O)n, has a major influence on the observed ion mobility and reactivity of the primary ions. Dynamic cluster formation and dissociation processes take place throughout the drift tube. Numerical simulations and the extensive experimental work 1, 2, 3 made it possible to characterize the chemical kinetics taking place. The population of the primary ions (NO+, O2+, H3O+) is strongly dependent on the external conditions such as reduced field strength or the water mixing ratio. Furthermore, the measured drift time can be influenced by resonant charge transfer. Coupled chemistry-transport simulations with the Ion Dynamics Simulation Framework (IDSimF) developed in the Benter group agree very well with the experimental data.
Based on the results obtained, a continuation project has now been started to deepen the knowledge of the field-strength-dependent reaction kinetics of ion-molecule clusters using other ionization methods in addition to corona discharge (high cathode discharges and, in particular, laser-assisted photoionization).
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Reduction of nitrogen oxide pollution in the vicinity of road tunnels with the aid of photocatalytic reactors ("TunNOX")
The aim of this project is to investigate ways of reducing NOx pollution in the exhaust air from road tunnels. The aim is to gain knowledge about the use of linear photocatalytic reactors that can be integrated into the exhaust air system of tunnels. In addition to findings on the integration of this innovative technology in new tunnels, the focus is on the possibility of retrofitting existing tunnels. The investigations include analyses of the availability of the technologies, the integration capability, the adaptability to the requirements in the event of operation and fire, the effectiveness of exhaust air purification and the assessment of the cost-benefit ratio.
Joint research project as part of the "Road Innovation Program" of the Federal Highway Research Institute (BAST)
Partner:
- RWTH Aachen University, Institute for Road Engineering Aachen (ISAC)
- RWTH Aachen University, Aerodynamic Institute (AIA)
- Aachen Engineering Company for Roads (ISAC GmbH)
- University of Wuppertal (BUW), Physical and Theoretical Chemistry
Project manager BUW: PD Dr. Jörg Kleffmann
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Ion Dynamics Simulation Framework (IDSimF)
The Ion Dynamics Simulation Framework (IDSimF) is an open tool for simulating the motion and chemical dynamics of molecular ions. The primary application is the modeling of the dynamics of chemically reactive ions in ion sources and inlet systems of atmospheric pressure ionization mass spectrometers (API-MS), ion mobility analyzers and mass analyzers. IDSimF offers in particular the possibility to consider electrical particle-particle interactions (space charge) and the interaction with neutral background gas. An integrated model for describing the chemical kinetics of the simulated ions also allows their reactivity to be taken into account. IDSimF and a companion package, IDSimPy, have been placed under an open source license so that the source code is publicly available and modifiable. This allows any user to extend IDSimF and adapt it to their own problems.
IDSimF source code repository IDSimPy source code repository