Coverage and temperature-dependent behavior of potassium on Pd(110)

Physical Review B - Condensed Matter and Materials Physics

Volumn 68, Issue 23, 2003, Pages

  Pratt, S J ^a   Escott, D K ^a   King, D A ^a  

^a UNIVERSITY OF CAMBRIDGE   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

PALLADIUM; PALLADIUM 110; POTASSIUM; UNCLASSIFIED DRUG;

ADSORPTION; ARTICLE; AUGER ELECTRON SPECTROSCOPY; CALIBRATION; CHEMICAL ANALYSIS; CRYSTAL; DESORPTION; ELECTRON DIFFRACTION; TEMPERATURE DEPENDENCE;

EID: 0842343400     PISSN: 10980121     EISSN: 1550235X     Source Type: Journal    
DOI: 10.1103/PhysRevB.68.235406     Document Type: Article

References (41)

1. R.L. Gerlach and T.N. Rhodin, Surf. Sci. 19, 403 (1970).
2. A. Berkó and F. Solymosi, Surf. Sci. 187, 359 (1987).
3. M.P. Kiskinova, in Poisoning and Promotion in Catalysis Based on Surface Science Concepts and Experiments, edited by B. Delmon and J. Yates, Jr. (Elsevier, Amsterdam, 1992), Vol. 70, p. 19.
4. R.D. Diehl and R. McGrath, Surf. Sci. Rep. 23, 43 (1996).
5. R.D. Diehl and R. McGrath, J. Phys.: Condens. Matter 9, 951 (1997).
6. I. Langmuir, J. Am. Chem. Soc. 54, 2798 (1932).
7. R.W. Gurney, Phys. Rev. 47, 479 (1935).
8. S.J. Jenkins and D.A. King, Chem. Phys. Lett. 317, 372 (2000).
9. C.J. Barnes, in The Chemical Physics of Solid Surfaces, edited by D.A. King and D.P. Woodruff (Elsevier, Amsterdam, 1994), Vol. 7, p. 501.
10. R.J. Behm, in Physics and Chemistry of Alkali Metal Adsorption, edited by H.P. Bonzel, A.M. Bradshaw, and G. Ertl (Elsevier, Amsterdam, 1989), Vol. 57, p. 111.
11. C.J. Barnes, M. Lindroos, D.J. Holmes, and D.A. King, in Physics and Chemistry of Alkali Metal Adsorption (Ref. 10), p. 129.
12. C.J. Barnes, M.Q. Ding, M. Lindroos, R.D. Diehl, and D.A. King, Surf. Sci. 162, 59 (1985).
13. C.J. Barnes, M. Lindroos, and D.A. King, Surf. Sci. 201, 108 (1988).
14. H. Hörnis and E.H. Conrad, Surf. Sci. 322, 256 (1995).
15. S.J. Pratt and D.A. King, Surf. Sci. 540, 185 (2003).
16. R. Raval, M.A. Harrison, and D.A. King, J. Vac. Sci. Technol. A 9, 345 (1991).
17. M.A. Harrison, Ph.D. thesis, University of Liverpool, 1989.
18. T. Matsushima, J. Phys. Chem. 91, 6192 (1987).
19. R.J. Behm, D.K. Flynn, K.D. Jamison, G. Ertl, and P.A. Thiel, Phys. Rev. B 36, 9267 (1987).
20. C.J. Barnes, P. Hu, M. Lindroos, and D.A. King, Surf. Sci. 251/252, 561 (1991).
21. T. Matsuda, C.J. Barnes, P. Hu, and D.A. King, Surf. Sci. 276, 122 (1992).
22. W.A. Coghlan and R.E. Clausing, At. Data 5, 317 (1973).
23. J. Lehmann, P. Roos, and E. Bertel, Phys. Rev. B 54, R2347 (1996).
24. G.E. Rhead, M.G. Barthès-Labrousse, and C. Argile, Thin Solid Films 82, 201 (1981).
25. C. Argile and G.E. Rhead, Surf. Sci. Rep. 10, 277 (1989).
26. C.J. Barnes, PhD. thesis, University of Liverpool, 1987.
27. C. Argile, M.G. Barthès-Labrousse, and G.E. Rhead, Surf. Sci. 138, 181 (1984).
28. S.D. Parker and P.J. Dobson, Surf. Sci. 171, 267 (1986).
29. A.J. Dekker, in Solid State Physics, edited by F. Seitz and D. Turnbull (Academic Press, New York, 1958), Vol. 6, p. 251.
30. C. Argile and G.E. Rhead, Surf. Sci. 203, 175 (1988).
31. C. Argile and G.E. Rhead, Surf. Sci. 279, 244 (1992).
32. G.A. Somorjai, Introduction to Surface Chemistry and Catalysis (Wiley, New York, 1994).
33. D. Lackey and D.A. King, J. Chem. Soc., Faraday Trans. 1 83, 2001 (1987).
34. P. Atkins, Physical Chemistry (Oxford University Press, Oxford, 1990).
35. CRC Handbook of Chemistry and Physics (CRC Press, Boca Raton, FL, 1999).
36. D.A. King, Surf. Sci. 47, 384 (1975).
37. G.A. Attard and C.J. Barnes, Surfaces (Oxford University Press, Oxford, 1998).
38. J.B. Hannon, M. Giesen, C. Klunker, G.S. IckingKonert, D. Stapel, H. Ibach, and J.E. Muller, Phys. Rev. Lett. 78, 1094 (1997).
39. C. Klünker, C. Steimer, J.B. Hannon, M. Giesen, and H. Ibach, Surf. Sci. 420, 25 (1999).
40. In Ref. 1, the authors conclude that for Na on Ni(111) and Ni(110) the second Na layer apparently begins to form before the first layer is complete. We question how they have reached this conclusion, as it is not clearly explained. It seems that they assume the desorption peak near 380 K for Na on Ni surfaces to be entirely due to multilayer Na. For Na on Ni(110), Ref. 1, Fig. 10, this peak starts to develop already at coverage D, before the peak near 500 K (the lowest temperature peak that they associate with the first layer) is saturated. This is an example of diffusion-limited adsorption, as equilibrium is not attained at coverage D. However, we find for K on Pd(110) through correlated TPD and crystal current measurements that 0.23 ML K atoms adsorbed in the first layer desorb at the same temperature as multilayer K. As the saturated first layer coverage is 0.6 ML, this means that more than a third of the first layer atoms desorb at the same temperature as the multilayer. The situation may or may not be similar for Na on Ni and other systems, but in view of our findings, we conclude that the TPD data alone in Ref. 1 cannot reliably indicate the precise coverage at which the Na multilayer begins to form. It is possible that first layer and multilayer Na peaks overlap, as we have found for K on Pd(110). Thus it is not clear whether it is second layer or further first layer adsorption that begins before the peak near 500 K is saturated at coverage D. The authors of Ref. 1 also suggest (p. 416) that a doublet of peaks in the desorption spectrum of Na from Ni(100) (Fig. 13) is composed of distinct desorption signals from second and third layer Na atoms. The absence of this feature for Na on Ni(111) and Ni(110) therefore implies that there is not much difference in binding energy of second and third layer Na on these substrates (not first and second layer Na, as the authors write).
41. W. Brown, R. Kose, and D.A. King, Chem. Rev. (Washington, D.C.) 98, 797 (1998).