Magnetic properties of Hydrogenated Li and Co doped ZnO nanoparticles

TL;DR

This study investigates how hydrogenation affects the magnetic properties of Li and Co doped ZnO nanoparticles, revealing temperature-dependent ferromagnetism and the role of cobalt clusters in magnetic behavior.

Contribution

It demonstrates that hydrogenation at different temperatures induces distinct magnetic states in doped ZnO nanoparticles, highlighting the intrinsic and extrinsic origins of ferromagnetism.

Findings

Room temperature hydrogenation induces weak ferromagnetism.

High-temperature hydrogenation results in robust ferromagnetism.

Reheating in air reverts samples to paramagnetic state.

Abstract

The effect of hydrogenation on magnetic properties of Zn0.85Co0.05Li0.10O nanoparticles is presented. It was found that the sample hydrided at room temperature (RT) showed weak ferromagnetism (FM) while that hydrided at 400oC showed robust ferromagnetism at room temperature. In both cases reheating the sample at 400oC in air converts it back into paramagnetic state (P) completely. The characterization of samples by X-ray and electron diffraction (ED) showed that room temperature ferromagnetism observed in the samples hydrogenated at RT is intrinsic in nature whereas that observed in the samples hydrogenated at 400oC is partly due to the cobalt metal clusters.