Experimental and theoretical study of the Ni−(m-ZrO2) interaction

► Interfacial phase Ni7Zr2 is evidenced by XRD patterns in the Ni/ZrO2 catalysts. ► An increase amount of inserted nickel enhances the insertion energy. ► Nickel insertion is accompanied by a lattice expansion and reduction of symmetry. ► A large fraction of the charge loses by Ni Atoms is transferred to the Zr cations. ► Penetration of Ni atoms inside the oxide is easier across the surface (1¯01) than through the surface (1¯11).