Once only possible at national labs, near-ambient-pressure XPS is now available at Lehigh University using a new SPECS DeviSim NAP reactor cell coupled with a PHOIBOS 150 NAP electron energy analyzer.
X-rays from an Al Kα source impinge on the sample through a thin Si3N4 membrane in the environmental cell. A portion of the photoelectrons enter the electron analyzer through a small aperture. Gas particles are removed by a series of pumps before reaching the detector. Ionized gas atoms or molecules replenish the electronic charge that has left the surface, mitigating sample charging.
Applications
- In operando measurements of catalysts
- Characterization of biological materials and other non-vacuum-compatible samples
- Measurements of surface-gas or surface-liquid interfaces
Sample Preparation
- In situ gas dosing up to 1 mbar
- Heating up to 600°C
- Ar sputter depth profiling
Further Reading
https://www.specs-group.com/nc/specsgroup/knowledge/methods/detail/nap-xps-and-nap-ups/
Synonyms and related techniques
- Electron Spectroscopy for Chemical Analysis (ESCA)
- Photoemission Spectroscopy (PES)