Charge-transfer-driven enhanced room-temperature ferromagnetism in BiFeO$_3$/Ag nanocomposite

TL;DR

This study demonstrates a significant enhancement in room-temperature ferromagnetism in BiFeO₃/Ag nanocomposites due to charge transfer effects, promising for biomedical and other applications.

Contribution

It reveals that charge transfer between Ag and O in BiFeO₃/Ag nanocomposites dramatically increases ferromagnetism at room temperature, a novel finding.

Findings

Over an order of magnitude increase in saturation magnetization.

Charge transfer between Ag and O is key to magnetic enhancement.

Potential applications in biomedical fields.

Abstract

We report observation of more than an order of magnitude jump in saturation magnetization in BiFeO$_3$/Ag nanocomposite at room temperature compared to what is observed in bare BiFeO$_3$ nanoparticles. Using transmission electron microscopy together with energy dispersive x-ray spectra (which maps the element concentration across the BiFeO$_3$/Ag interface) and x-ray photoelectron spectroscopy, we show that both the observed specific self-assembly pattern of BiFeO$_3$ and Ag nanoparticles and the charge transfer between Ag and O are responsible for such an enormous rise in room-temperature magnetization. The BiFeO$_3$/Ag nanocomposites, therefore, could prove to be extremely useful for a variety of applications including biomedical.