Strongly Fluorescent Quaternary Cu−In−Zn−S Nanocrystals Prepared from Cu₁-ₓInS₂ Nanocrystals by Partial Cation Exchange [Strongly Fluorescent Quaternary Cu-In-Zn-S Nanocrystals Prepared from Cu1-xInS2 Nanocrystals by Partial Cation Exchange]

We report a high-yield, low cost synthesis route to colloidal Cu 1-xInS 2 nanocrystals with a tunable amount of Cu vacancies in the crystal lattice. These are then converted into quaternary Cu-In-Zn-S (CIZS) nanocrystals by partial exchange of Cu + and In 3+ cations with Zn 2+ cations. The photoluminescence quantum yield of these CIZS nanocrystals could be tuned up to a record 80%, depending on the amount of copper vacancies. © 2012 American Chemical Society.