A Study on Coalescence of Semiconductor Nanocrystals for Functional Nanostructures

Abstract

Exploiting colloidal semiconductor nanocrystals (NCs) as a building block for hierarchical nanostructures can expand the nanoscience field. Hence, it is a big challenge for nanoscience research to understand the control of coalescence of colloidal semiconductor NCs passivated with surface ligands. In this study, facile approach for activating the CdSe NC’s surface by controlled stripping the carboxylate ligands with an alkylammonium–selenide complex for coalescence was investigated. The surface of as-prepared CdSe NC became sparsely passivated and stoichiometric through the addition of alkylamine and elemental Se; subsequently, coalescence readily occurred. Controlled coalescence or hierarchical heteronanostructures can be obtained by sophisticated control of the surface state of NCs. it is anticipated that the surface-activated colloidal semiconductor NCs will perform as a promising nanoscale building block to fabricate functional nanostructures. Using a protocol described in this study, it is possible to not only understand the nature of coalescence, but to also construct hierarchical heteronanostructures.