| AVS 59th Annual International Symposium and Exhibition | |
| Surface Science | Tuesday Sessions |
| Session SS-TuP |
| Session: | Surface Science Poster Session |
| Presenter: | E. Ginting, University of Wyoming |
| Authors: | J. Zhou, University of Wyoming E. Ginting, University of Wyoming Y.H. Zhou, Xiamen University, China |
| Correspondent: | Click to Email |
Ceria has attracted great attentions in catalysis due to its unique redox properties and oxygen storage capacity. To improve the properties of ceria, suitable metal dopants such as Ti and Mn can be incorporated into it and form dopant-ceria mixed oxides. The additional metal component can modify the physical/chemical properties of ceria. To understand the intriguing chemistry at the metal dopant-ceria interfaces, we examined their structures at the nano-scale using X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM) techniques. Dopants including Ti and Mn were vapor-deposited onto well-ordered reducible CeO2(111) thin films grown on Ru(0001) under ultrahigh vacuum conditions. Both Mn and Ti are oxidized at the cost of ceria reduction upon deposition at 300 K. Ti is in the +4 formal oxidation state. However, +2 state of Mn is the predominate species on ceria. STM studies show the formation of two-dimensional structures on ceria which can further develop into chain structures or triangular domains upon heating. Our studies suggest a strong interaction between metal dopants and ceria. The nature of dopant-ceria interfaces greatly depends on the dopant type. The research is sponsored by the School of Energy Resources at University of Wyoming.