OXIDATION OF LANTHANUM OVERLAYERS ON CU(111)

被引:22
作者
DEASHA, AM [1 ]
NIX, RM [1 ]
机构
[1] UNIV LONDON QUEEN MARY & WESTFIELD COLL, DEPT CHEM, LONDON E1 4NS, ENGLAND
关键词
COPPER; EPITAXY; GROWTH; LANTHANIDES; LANTHANUM OXIDE; LOW ENERGY ELECTRON DIFFRACTION (LEED); OXIDATION; X-RAY PHOTOELECTRON SPECTROSCOPY;
D O I
10.1016/0039-6028(95)90015-2
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The oxidation of ultrathin lanthanum overlayers on Cu(111) has been studied by XPS, ISS, TPD and LEED. At 300 K the deposited La films are readily oxidised by exposure to O-2 to give a disordered La2O3 film. This oxide may then be ordered by annealing at over 700 K in vacuum, producing a surface analogous to La2O3(001). Further heating in a low pressure of oxygen induces an irreversible structural transformation to a more complex oxide structure which still exhibits a coincidence relationship with the substrate. All the oxide films are stable to 873 K, after which a gradual reduction in the apparent surface La and O concentrations is observed.
引用
收藏
页码:41 / 50
页数:10
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