Study on Formation Mechanism by Monitoring the Morphology and Structure Evolution of Nearly Monodispersed Fe3O4 Submicroparticles with Controlled Particle Sizes

Abstract

We present a facile surfactant-free solvothermal method for the fabrication of nearly monodispersed Fe3O4 submicroparticles with tunable particle sizes ranging from 130 to 420 nm by varying the concentration of single iron source FeCl3·6H2O in initial solutions. The morphology and crystal structure of the as-prepared Fe3O4 submicroparticles have been well characterized by using SEM/TEM/HRTEM, XRD, FT-IR, Raman spectroscopy, and XPS methods. It is found that the Fe3O4 particles present single-crystal nature and strong ferromagnetic property with magnetization saturation values ranged in 54.3–88.7 emu·g–1. A complexation–aggregation–phase transformation formation mechanism was first proposed for the nearly monodispersed single-crystal Fe3O4 submicroparticles based upon the quasi-in situ monitoring of the morphology and structure evolution of the samples during the synthesis process. These size-tunable nearly monodispersed Fe3O4 submicroparticles are expected to have promising applications in wide research f...