Morphology control of CdSe submicrostructures with high hierarchy in solution

摘要

A series of CdSe submicrostructures, including rods, fringy structures, and fasciculate tubes with high hierarchy, have been selectively prepared by a facile one-step solution-based strategy without using any organic surfactants, simply by changing the feeding quantity of aqueous ammonia (25% NH3). The growth mechanism based on kinetic control is discussed for the selective formation of the CdSe submicrostructures with special morphologies. In the present reaction system, ammonia plays a dual role: providing an alkaline medium for the formation of Se2- and acting as a coordinating agent for cadmium cations in either the solution or the solid phase. The feeding quantity of aqueous ammonia greatly influences the rate of formation of the Se2- anion, and thus determines the final morphology of CdSe crystals. Compared with previous methods of preparing CdSe structures, this concise and novel one-step route has special advantages, suggesting a new path for convenient synthesis of CdSe materials with novel morphology. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)