Measurement of the giant magnetoresistance effect in cobalt-silver magnetic nanostructures: nanoparticles.

Cobalt-silver (Co-Ag) core-shell nanoparticles with different silver thicknesses were prepared by the microemulsion method in a two-step reduction process. Transmission electron microscopy (TEM) characterization revealed the almost monodispersity and nanometric size (in the range 3-5 nm depending on the shell thickness) of the synthesized nanoparticles. However, it was the use of high-resolution TEM that revealed the correct core-shell formation of the nanometric material.