Abstract
Iron oxide nanoclusters, exhibiting unusual and interesting particle characteristics on thermal treatment, have been synthesized and studied. In all samples, a sharp size distribution has been obtained. Initially, the clusters exhibit agglomerated fractal morphology with low compactness but these disintegrate into smaller fragments and then grow in size as a function of the holding time of thermal treatment. The structure becomes more compact at higher holding times. The monodispersed agglomerates are basically clusters consisting of a large number of smaller grains of a few nanometres in size. The fractions of interfacial and bulk components in all samples have been estimated.