Research 15: B Ingham

1. A synchrotron EXAFS and XRD study of nickel carbon materials for fuel cell catalysis Bridget Ingham, IRL NZIP conference, 19 October 2011

4. X-ray diffraction

5. X-ray diffraction: results As-prepared

6. X-ray diffraction: results After electrochemical treatment

7. Ni 3 C? S. Nagakura, J. Phys. Soc. Jap. 12 (1957) 482; 13 (1958) 1005 Electron diffraction is more sensitive to C relative to Ni than X-ray diffraction.

8. X-ray absorption spectroscopy Sample (working electrode) (O 2 ) (Thermometer) (Heating tape) Reference electrode Counter electrode

9. Data extraction EXAFS

10. EXAFS models Ideally, create a model from a known crystal structure -> the fitted parameters show the average local deviation from the crystal structure (bond distances, co-ordination #s)

11. EXAFS models What if no crystal structure exists? Single shell theory…

12. Results ‘ Low’ ‘ Medium’ ‘ High’

13. Summary

14. Summary

15. Summary ‘ High’ ‘ Medium’ ‘ Low’

17. Acknowledgements Cambridge University, UK Kieran Fahy, Xiao Yao Chin, Eric Rees, Gareth Haslam, Zoe Barber, Tim Burstein Imperial College London, UK Mary Ryan Industrial Research Ltd, NZ Nicola Gaston, Christian Dotzler NSLS and BNL Hugh Isaacs, Kenneth Sutter, Larry Fareria, Mike Sansone Funding NZ FRST (NERF) C08X0409 EPSRC Portions of this research were undertaken on the Powder Diffraction beam line at the Australian Synchrotron, Victoria, Australia and beam line X10C at the National Synchrotron Light Source. Use of the National Synchrotron Light Source, Brookhaven National Laboratory, was supported by the U.S. Department of Energy, Office of Basic Energy Sciences.