Synthesis and study of magnetic properties of high temperature stable Ni nanoparticles in a nearly amorphous AlPO4 matrix in an oxidative atmosphere

Graphitized carbon coated Ni nanoparticles were synthesized in an AlPO4 matrix in situ in an oxidative atmosphere without using any foreign reducing agent. The Ni nanoparticles were evenly distributed in an inactive AlPO4 matrix and protected from the oxidation in air up to 900 °C. Carbon coating over the nanoparticles remained intact even when the samples were calcined at 900 °C in air. Magnetization of the Ni nanoparticles in the composite approached ∼89% of their bulk magnetization value when calcined at 900 °C in air. Magnetization increased with increasing the calcination temperature up to 900 °C.