Optical and magnetic properties of Ni nanoparticles in rutile formed by Ni ion implantation

Abstract

Crystalline Ni nanoparticles in the near surface of TiO2 (rutile) have been synthesized by Ni ion beam implantation at room temperature to a fluence of 1× 1017 cm2. Transmission electron microscopy, optical absorption spectroscopy, and a superconducting quantum interference device magnetometer have been utilized to characterize the nanostructure, optical and magnetic properties of Ni particles in TiO2. Crystalline Ni nanoparticles with dimensions ranging 3-20 nm formed in the near surface of rutile, which caused a broad absorption band from 700 nm in the optical absorption spectrum. Magnetic measurement indicated that the coercive force of Ni nanoparticles was about 210 Oe at 10 K. The superparamagnetism of the nanoparticles was observed above blocking temperature T=85 K. © 2006 American Institute of Physics.