Magnetite nanoparticle orientation mapping from a 4D STEM dataset

Gatan instrument used

The K3^® IS camera delivers simultaneous low-dose imaging via real-time electron counting, fast continuous data capture, and a large field of view. In a 4D STEM experiment, the STEMx^® system precisely synchronizes the speed of the scanning probe to the camera frame rate to enable high-speed data acquisition and eliminates the potential for data loss.

Background

Magnetite (Fe₃O₄) nanoparticles are promising magnetic materials for hyperthermia, MRI contrast agents, and as magnetic cores in high switching frequency inductors and transformers. In each of these applications, a strong magnetic saturation (M_sat) is necessary. Recent studies show that the presence of antiphase boundaries (internal defects) can significantly reduce this value. Identifying optimal synthetic conditions is useful to produce high-quality NPs with M_sat approaching maximum bulk values.