First-principles study on the structural and electronic properties of clean and atomic oxygen adsorbed ZrC(0 0 1) surface

The structural and electronic properties of clean and atomic oxygen adsorbed ZrC(0 0 1) surface have been investigated by first-principles calculations using the plane-wave pseudopotential method. A ZrC(0 0 1) slab surface model containing 7 layers of Zr(C) atoms and a vacuum of 10 Å is constructed. It is found that the C atoms of clean ZrC(0 0 1) surface move inward instead of outward after structural relaxation, and the surface relaxation is weak and has little effect on the electronic properties of the clean surface model. For an atomic oxygen adsorbed ZrC(0 0 1) surface, it is concluded that MMC site is the most stable adsorption site, and the surface C rather Zr atoms will play a major role in determining the oxidation behavior of ZrC(0 0 1) surface. The present calculations are helpful for the microscale study on the oxidation mechanism of bulk ZrC.