Structural and magnetic properties of match-like Ni/ZnO compound nanorod array

• Ni films were sputter-deposited on ZnO nanorod arrays.
• The Ni/ZnO compound nanorod arrays are formed.
• The compound nanorods have the match-like structure.
• The Ni granule at the nanorod top consists of many fine granular grains.
• The compound nanorod arrays exhibit the ferromagnetic behavior.

This work attempts to prepare Ni/ZnO compound nanorods with both ferromagnetic and semiconducting properties. ZnO nanorod array was grown on the ZnO:Al-coated glass substrate by using a chemical method. Ni film was sputter-deposited on the ZnO nanorod array to form the Ni/ZnO compound nanorod array. The compound nanorods grow perpendicular to the substrate surface and have a match-like structure, i.e., the large Ni granule is formed on the top surface of the ZnO nanorod. The ZnO nanorods have the c-axis wurtzite structure in the nanorod growth direction. The Ni granules consist of many fine granular grains and exhibit a ferromagnetic behavior. The magnetic hysteresis loop at the magnetic field applied in the direction parallel to the substrate surface exhibits an easy magnetization compared with that at the magnetic field applied in the direction perpendicular to the substrate surface.