Incorporation of cobalt into ZnO nanoclusters

TL;DR

This study investigates the structural, optical, and magnetic properties of Co and Al co-doped ZnO nanoclusters, revealing substitutional Co incorporation and paramagnetic behavior in nanostructured films.

Contribution

It presents a detailed analysis of Co and Al co-doping effects on ZnO nanoclusters, including synthesis, structural characterization, and magnetic properties, which is novel in this context.

Findings

Co ions are substitutionally incorporated into ZnO nanoclusters.

The nanoclusters exhibit paramagnetic behavior following Curie law.

The films have highly oriented wurtzite structure with 50-100 nm size.

Abstract

The structural, optical and magnetic properties of nanostructured ZnO films co-doped with cobalt and aluminium have been studied. The nanocrystalline films, with cluster sizes in range 50 - 100 nm, were deposited by pulsed laser ablation in a mixed atmosphere of oxygen and helium. The nanocrystallites have the wurtzite structure and are highly oriented with the c-axis perpendicular to the substrate. Both optical and electron spin resonance (ESR) spectroscopy results show the substitutional incorporation of Co$^{2+}$ ions on the Zn site inside the ZnO nanoclusters. The temperature dependence of the ESR spectra follows Curie law corresponding to a paramagnetic material.