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Updated: Feb 27, 2026
11:59
High-speed Particle Image Velocimetry Near Surfaces
Published on: June 24, 2013
33.9K
Ion and velocity map imaging for surface dynamics and kinetics.
Dan J Harding1, Jannis Neugebohren1, Hinrich Hahn1
1Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstraße 6, 37077 Göttingen, Germany.
The Journal of Chemical Physics
|July 10, 2017
Summary
A new instrument uses ion imaging to precisely measure molecular interactions on surfaces. This allows for faster, more accurate studies of surface desorption kinetics and scattering velocities.
Area of Science:
- Surface science
- Chemical kinetics
- Physical chemistry
Background:
- Studying molecular beam-surface interactions is crucial for understanding chemical reactions and material properties.
- Previous methods for measuring surface desorption kinetics and scattering velocities were limited in accuracy and speed.
- Independent determination of residence times and scattering velocities is essential for true kinetic analysis.
Purpose of the Study:
- To introduce a novel instrument for studying molecular beam-surface scattering and surface desorption kinetics.
- To enable independent determination of surface residence times and desorbing molecule velocities.
- To accelerate data acquisition for molecular beam kinetics studies.
Main Methods:
- Utilizes ion imaging to analyze molecular beam-surface interactions.
- Employs non-resonant multiphoton ionization with a 150-fs near-IR laser pulse for broad detection.
- Demonstrates compatibility with velocity map imaging techniques.
Main Results:
- Achieved independent measurement of surface residence times and scattering velocities.
- Enabled derivation of true kinetic traces (product flux vs. residence time).
- Successfully characterized desorption kinetics of CO on Pd(111) and Pt(111), obtaining pre-exponential factors and activation energies.
Conclusions:
- The new instrument significantly advances the study of surface desorption kinetics.
- Provides a more general and accelerated method for molecular beam kinetics research.
- Offers a powerful tool for detailed surface interaction analysis.
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