Optical Properties of Monodispersed Spherical Aggregates Formed by Self‐Assembly of ZnS Nanoparticles

ZnS nanoparticles of diameters between 3–4 nm were aggregated to form dense nanospheres of sizes ∼100 nm by a colloidal precipitation method using PVP as the stabilizing agent. XRD studies showed that the ZnS nanoparticles were of zinc blend (cubic) structure. It was observed that the dense nanospheres had a tendency to form supramolecular nanostructures on a solid substrate upon solvent evaporation. The resulting films had highly ordered structures with the aggregated nanospheres interconnected to form dendrite like structures and chains of micrometer length scale. Optical absorption spectra of the samples demonstrated the effect of quantum confinement in the ZnS nanocrystals. Photoluminescence measurements showed a sharp UV emission at ∼370 nm.

The authors like to express their sincere gratitude for the financial help from Department of Science and Technology, Government of India during the execution of the work in the nano‐initiative program.