On the Mechanism of Lead Chalcogenide Nanocrystal Formation

J. Am. Chem. Soc., 128 (40), 13032 -13033, 2006. 10.1021/ja062626g S0002-7863(06)02626-6
Web Release Date: September 16, 2006

On the Mechanism of Lead Chalcogenide Nanocrystal Formation

Jonathan S. Steckel, Brian K. H. Yen, David C. Oertel, and Moungi G. Bawendi*

Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139

mgb@mit.edu.

Received April 19, 2006

Abstract:

On the basis of evidence from ³¹P NMR spectroscopy, and using PbSe as a model, we propose two simultaneous mechanisms through which "monomers" are formed in preparations of lead chalcogenide nanocrystals (NCs). In one mechanism, selenium is delivered as a Se^2- species, whereas in the other, Se⁰ reacts with metal already reduced by the organophosphine. This latter mechanism helps explain the sensitivity of NC preparations to the purity of organophosphines and allows the rational modification of batch NC reactions to increase yield.

Download the full text: PDF | HTML