A first-principles study on the adhesion of Pt layers to NiO(100) and IrO2(110) surfaces

摘要

We report a comparative study on the Pt/NiO and Pt/IrO2 interfaces from first principles. It is found that Pt layers can bind with the IrO2 surface much stronger than the NiO surface. The adhesion strength of Pt/NiO interfaces is dominated by the Pt-O ionic bond. The Pt layers induce corrugation of the oxide surfaces and loosen the Ni-O bonding strength. The dissolution of Ni atoms into the Pt slab appears to enhance the adhesion strength by forming stronger Ni-O bonds. In contrast, the adhesion strength of Pt/IrO2 interfaces has contributions from both Pt-O ionic and Pt-Ir metallic bonds. Furthermore, the interfacial adhesion of IrO2/NiO is also stronger than that of Pt/NiO interfaces. IrO2 may work as glue layers to stabilize Pt/NiO films.