Synthesis and characterization of FePt/Au core-shell nanoparticles

TL;DR

This study synthesizes gold-coated FePt nanoparticles, analyzing how gold coating affects their structural and magnetic properties, revealing significant changes in coercivity and blocking temperature due to surface modifications.

Contribution

It presents a method for synthesizing FePt/Au core-shell nanoparticles and investigates the impact of gold coating on their magnetic behavior, which is a novel insight.

Findings

Gold coating increases particle diameter from 4 to 10 nm.

Coercive field decreases threefold with gold coating.

Blocking temperature is halved by gold coating.

Abstract

In this work, the structural and magnetic properties of the gold-coated FePt nanoparticles synthesized from high-temperature solution phase are presented. The amount of gold was optimized to obtain most of the FePt particles coated. The particle diameter increases from 4 to 10 nm as observed by TEM. The magnetic properties are largely affected by the coating. At low temperature, the coercive field Hc of the coated nanoparticles decreases about three times respect to the uncoated and the blocking temperature reduces to the half. The changes of the magnetic behavior are discussed in terms of the effect of the gold atoms at the FePt core surface.