Welcome to the near ambient pressure XPS (NAP-XPS) system page.


You will find information relevant to conducting near ambient pressure measurements below. This instrument is the latest addition to the Surface Analysis Laboratory (SAL) that aims to serve as a regional facility funded by the National Science foundation, College of Arts and Science and College of Engineering. The goal is to encourage all applicable users in the region from academia, industry and government in pushing the frontier of operando XPS measurements and encourage collaborations.


To schedule time on the NAP-XPS system users first must submit a proposal detailing the experiment they have in mind. It is strongly encouraged that users would thoroughly search the literature for work that supports their hypothesis. More information regarding scheduling can be found in the “Experiment Proposal” tab.

Purchase of the ambient pressure XPS was supported by that National Science Foundation through NSF MRI award 1625792.

For further questions and discussion, please contact Dr. Yehia Khalifa.

The system features the following capabilities:
  • Near ambient pressure cell capable of XPS measurements from UHV up to 20 mbar of N2
  • 3 Mass flow controllers and a separate leak valve (for vapors) in a premixing line prior to introduction to the cell
  • Al anode X-ray source with a variable spot size between 250 ┬Ám to 1 mm
  • 1-D DLD SPECS PHOIBOS NAP analyzer capable of 1 meV resolution
  • Sample cooling and heating covering the range of 200 K to 825 K
  • IQE 12/38 Argon Sputtering source for depth profiling and sputtering
Available Gases:
  • O2
  • CO
  • CO2
  • H2
  • H2O
  • Alcohols
  • Ar
  • N2
*Other gases would be considered upon discussion with the lab manager.


  • Sample size should not exceed 1.5 x 1.5 x 1 mm (L x W x H) in dimensions.
  • There is no charge neutralizer available therefore non-conductive samples will significantly charge.
  • Powder samples will only be secured via carbon tape. Samples utilizing carbon tape will be limited to room temperature measurements and non corrosive gases.

NAP-XPS Layout