On the mechanism of lead chalcogenide nanocrystal formation.
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 Se2- 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.
Steckel
Jonathan S
JS
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA.
Yen
Brian K H
BK
Oertel
David C
DC
Bawendi
Moungi G
MG