Investigation of the state of the electrochemically generated adsorbed O species on Au films interfaced with Y2O3-doped-ZrO2
- 32 Downloads
Adsorbed O species on Au interfaced with Y2O3-doped-ZrO2 are generated by electrochemical O2− supply. It was found that two oxygen chemisorbed states are formed, which desorb at 420 °C (state α) and 550 °C (state β) with activation energies of desorption ranging between 115–145 kJ/mol and 235–270 kJ/mol, respectively. The strong interaction of the β-state O species with the Au surface causes an over 600 mV increase in Au surface potential and work function while the α-state O species is formed at even more positive catalyst-electrode potential. State α is attributed to normally adsorbed atomic O while the more ionic state β is only created electro-chemically and is mainly responsible for the work function increase of the Au catalyst-electrode surface. Their desorption activation energies of both states decrease linearly with increasing catalyst-electrode potential with slopes of the order of four.
KeywordsWork Function Catalyst Film Desorption Activation Energy High Temperature Desorbing Surface Work Function
Unable to display preview. Download preview PDF.
- T. Hayakawa, K. Sato, T. Tsunoda, K. Suzuki, M. Shimizu and K. Takehira, J. Chem. Soc., Chem. Commun. 1743 (1994).Google Scholar
- C.G. Vayenas, M.M. Jaksic, S. Bebelis and S. Neophytides in: Modern Aspects of Electrochemistry (J.O' M. Bockris, B.E. Conway and R.E. White, Eds.), Number 29, p. 57 (1996).Google Scholar
- M.E. Schrader, Surf. Sci.78, L227 (1978).Google Scholar
- D.D. Eley, and P.B. Moore, Surf. Sci.76, L599 (1978).Google Scholar
- M.I. Florit, M.E. Martins, and A.J. Arvia, J. Electroanal. Chem.126, 255 (1981).Google Scholar
- R.R. Ford, and J. Pritchard, JCS Chemistry Commun. 362 (1968).Google Scholar
- S. Evans, E.L. Avans, D.E. Parry, M.J. Tricker, M.J. Walters, and J.M. Thomas, Faraday Trans. Chem. Soc. 97 (1974).Google Scholar
- M.A. Lazaga, D.T. Wickham, D.H. Parker, G.N. Kastanas, and B.E. Koel, in: Catalytic Selective Oxidation (J.W. Hightower, and S.T. Oyama, Eds.), p. 90. ACS, Washington, DC, 1993.Google Scholar
- D.H. Parker, and B.E. Koel, J. Vac. Sci. Technol.A8, 2585 (1990).Google Scholar