A method of preparing monodisperse MX semiconductor nanocrystals can include contacting an M-containing precursor with an X donor to form a mixture, where the molar ratio between the M containing precursor and the X donor is large. Alternatively, if additional X donor is added during the reaction, a smaller ratio between the M containing precursor and the X donor can be used to prepare monodisperse MX semiconductor nanocrystals.
FEDERALLY SPONSORED RESEARCh
 This invention was made with Government support under Grant No. DE-SC0010538 awarded by the U.S. Department of Energy are under Grant No. DMR-0819762 awarded by the National Science Foundation. The Government has certain rights in the invention.