Effects of high magnetic field on the growth and magnetic property of L10-FePtCu nanoparticles

Abstract

Developing a novel strategy for promoting the disorder–order transition of FePt nanoparticles (NPs) is helpful to improve magnetic and electrocatalytic properties of the FePt NPs. In this research, high magnetic field (HMF) was introduced to wet-chemical synthesis of the L10-FePt NPs. The effects of HMF on the growth and magnetic property of wet-chemical synthesized L10-FePtCu NPs were studied. Cu atoms preferred to occupy the Fe-site in L10-FePt lattice at 6 T HMF, which facilitated this disorder–order transition and increased the ordering degree of L10-FePtCu NPs. When the magnetic dipolar interaction energy was much higher than the thermal energy, the HMF also enhanced the orientation attachment of L10-FePtCu NPs along 〈001〉 direction, which would lead to the increasing of growing rate and the aligning of NPs. The HMF increased the coercivity of L10-FePtCu NPs by increasing the grain size and the ordering degree. This work provides a promising method for controlling the disorder–order transition, the attachment growth, and the magnetic property of wet-chemical synthesized NPs.