Single-crystal like mesoporous ZnO:Mn2+ nanorings of high optoelectronic quality formed by self-assembly of nanoparticles in an ultrasonic hydrolysis process

Unique ring-shaped single-crystal like mesoporous ZnO:Mn2+ nanostructures have been fabricated through ultrasound assisted hydrolysis of zinc and manganese precursors. Incorporation of manganese into the nanostructures induced soft ferromagnetic behaviour. The nanostructures are of high optoelectronic quality with little structural and electronic defects. A mechanism of formation of the novel porous structures is proposed. The presence of manganese in Mn2+ state with strong hyperfine splitting (89 G) promises the application of these porous nanostructures in designing nanometric spintronic devices.