In Situ Observation of Heterogeneous Growth of CdSe Quantum Dots: Effect of Indium Doping on the Growth Kinetics

In this study, the heterogeneous growth of CdSe nanoparticles is reported by using in situ fluorescence spectroscopy. In the heterogeneous growth regime, nanoparticles with well-defined and very different sizes can coexist in the solution. The average size and size distribution of the nanoparticles is primarily not controlled by the usual focusing-defocusing (Ostwald ripening) of particles, rather by the formation of "magic" sized particles. In these studies, the effects of indium doping from indium chloride on the growth kinetics, size, size distribution, as well as the quantum yield of the various particles in the growth solution is investigated. Specifically, it is shown that the indium atoms accelerate the dissolution of the magic sized CdSe nanoparticles, while the chloride ions seem to stabilize the magic size particles. The present result will help to improve the understanding of how a dopant atom can affect the growth kinetics of semiconductor nanoparticles.