The surface structures of clean and defective ZnO(10▪0) were studied by using ab initio plane wave density functional theory. Two models of surface defects were examined; an O vacancy within the surface Zn–O dimer and an O vacancy in the second layer of the material. Previous models of CO oxidation on this surface had invoked the formation of isolated second layer defects. It was shown here that the formation of such a defect cost 1.01eV more energy than did the formation of a vacancy within the dimer bond and hence models of catalytic activity that invoke the formation of isolated second layer defects need to be re-examined.

The Structure of Higher Defective ZnO (10▪0). A.Wander, N.M.Harrison: Surface Science, 2003, 529[3], L281-4