Anomalous Surface Compositions of Stoichiometric Mixed Oxide Compounds


  • Financial support from the German Science Foundation (grant no. Gr 1447/9) is gratefully acknowledged. We also thank the Federal Ministry of Education and Research for the supporting travel grants (reg. no. 05 ES3XBA/5), the staff of BESSY II for continuous support, Dr. O. Shekhah for participating in the synchrotron measurements, and Dr. O. P. Tkachenko for participating in the LEIS measurements. I.E.W. acknowledges the support of Department of Energy (DOE)-Basic Energy Sciences (grant DEF-G02-93ER14350) for financial support. L.E.B. acknowledges the CONICET (USA–Argentina) collaboration (res. no. 0060)) and Agencia Nacional de Promoción Científica (project PICTRedes 729/06). The authors gratefully acknowledge Prof. D. Buttrey, University of Delaware, for providing the K-free bismuth molybdate single-crystal materials.


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Coated: Surface analytical studies (including low-energy ion scattering (LEIS)) show that the outer surface of bulk, stoichiometric mixed vanadates and molybdates can be strongly enriched with VOx or MoOx species. Such surface reconstruction even in the calcined initial state has implications for the discussion of catalytic and other materials properties.