Deciphering the Structural Evolution and Growth Mechanism of 3D β-In2S3 Nanostructures

The current work is an innovative study describing the growth mechanism of beta-In2S3 nanoclusters, built from single-nanodots, which are self-assembled into three-dimensional branched structures, evolving into nanourchins, nanoflowers, and nanoplatelets over the reaction time. Experimental evidence indicated that nanourchins are composed of In2S3 cores surrounded by In-rich spikes protruding from the surfaces. With time, the nanourchins undergo elemental redistribution in the presence of a sulfur precursor, resulting in the formation of hollow core/shell nanoflowers with In2S3/InS composition. Finally, the nanoflowers disintegrated into loosely connected nanoplatelets. A thorough study also exposed the hidden role of ligands in branching the structures, with short ligands positioned at a nanourchin's core and long ligands at the surface. The achievement of control over composition and branching is of great importance for tailoring a unique morphology for specific applications, like blocking layers in solar cells, photocatalysis, and chemical sensors.