Workshop Exercises: Advanced Chemical State Analysis

1) Carbon 1s - Set up a standard file for the fitting of adventitious carbon. Download the C 1s spectrum here.

2) Use it to charge correct a series of spectra. Download test file.

3) Oxygen 1s - General fitting of the O 1s spectra for metals.  Use file from number 2. Fit the O 1s spectrum, understand and explain all sources of oxygen.

4) Ti 2p - Set up curve-fitting parameters.  Download Ti 2p test file. See titanium literature fitting values.

5) Cr 2p - Set up curve-fitting parameters. Download Cr 2p test file. See chromium literature fitting values.

•Cr(VI) Species – mix of oxide and hydrated species
   -One narrow peak FWHM 1.5 eV
  -Range from 579.0 to 580.0 eV
•Cr(III) Species – mix of oxide and hydrated species
  -Cr(OH)3 - One broad peak FWHM of ~2.5 eV, set to 577.5 eV
  -Cr2O3 - Five multiplet peaks of equal FWHM (~0.9 eV) with set areas and separations based on standard sample
•Cr(0) – Metal
  -One asymmetric peak with a FWHM of 0.9 eV
  -Range from 573.9 to 574.5 eV

6) Ni 2p - For the brave, download and give it a try. See Ni 2p literature fitting values and general instructions here.

Workshop Exercises: The Auger Parameter and Wagner Plots

The Auger Parameter

1. Try calculating the Auger parameter for ZnO and Cd metal (click on links to download the spectra). (Compare to zinc and cadmium literature.)
2. Calculate the Auger parameter and use it to determine the chemical state for 3 unknown Cu species (Unknown 1, Unknown 2, Unknown 3).  Click here to access Cu binding energy and Auger parameter values.

Wagner Plots
Handouts will be given or you can download the exercise here.

Use lines of slope 1 and 3 to look at the trends:
1) For the Ga(III) halogen series.
2) Going from Ga(III), Ga(II) to Ga(I).
3) For the metal, alloys and semiconductors (Ga2O3 is also a semiconductor).
Do final state effects dominate (slope of 3) or do initial state effects dominate (slope of 1)?

XPS Reference Pages

This site contains information gained from decades of X-ray photoelectron spectroscopy (XPS) analyses of an enormous variety of samples analyzed at Surface Science Western laboratories located at the University of Western Ontario. Originally this site was designed as a place for students and our clients to access valuable tips and information. It has since been opened to all those interested in the XPS technique. Summaries of literature data, relevant references and unpublished data taken of well characterized standard samples are presented. Also curve-fitting tips, instrument set-up tips (specifically for the Kratos AXIS Ultra and Kratos AXIS Nova), and CasaXPS tips pertaining to questions we normally get from our students and clients, and other odd bits of information are presented.

XPS and Surface Science Western

The fine print:
Surface Science Western and the University of Western Ontario does not warranty any of the information shown at this site. Any use of this data in scientific publications or other forms should include referencing to the originally published data referenced herein.