title: Surface structural evolution in iron oxide thin films.
abstract: Ordered iron oxide ultrathin films were fabricated on a single-crystal Mo(110) substrate under ultrahigh vacuum conditions by either depositing Fe in ambient oxygen or oxidizing preprepared Fe(110) films. The surface structure and electronic structure of the iron oxide films were investigated by various surface analytical techniques. The results indicate surface structural transformations from metastable FeO(111) and O-terminated Fe(2)O(3)(0001) to Fe(3)O(4)(111) films, respectively. The former depends strongly on the oxygen pressure and substrate temperature, and the latter relies mostly upon the annealing temperature. Our experimental observations are helpful in understanding the mechanisms of surface structural evolution in iron oxides. The model surfaces of Fe-oxide films, particularly O-terminated surfaces, can be used for further investigation in chemical reactions (e.g., in catalysis).
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, PR China.
authors.forename: Mingshan
authors.initials: M
authors.lastname: Xue
authors.forename: Shuai
authors.initials: S
authors.lastname: Wang
authors.forename: Kehui
authors.initials: K
authors.lastname: Wu
authors.forename: Jiandong
authors.initials: J
authors.lastname: Guo
authors.forename: Qinlin
authors.initials: Q
authors.lastname: Guo