Mechanistic Insight and Optimization of InP Nanocrystals Synthesized with Aminophosphines

Abstract

We study the synthesis of indium phosphide quantum dots using InCl3, tris(dimethylamino)phosphine (P(NMe2)3), and oleylamine. We optimized the reaction conditions to reach high chemical yield (∼70%) and size control of the quantum dots with absorption maxima over all the visible range. Kinetic studies of the formation of the quantum dots show that, under certain conditions, the growth of nanoparticles seems to approach a LaMer type growth. We have used 31P NMR, mass spectroscopy, and DFT calculations to decipher the reaction mechanisms of InP formation at the molecular level. The mechanistic investigation is in good agreement with the conclusions drawn from the optimization of the synthetic conditions.