Monitoring of Mn ion ejection from CdSe host lattice

In this Letter, Mn-doped CdSe nanocrystals with zinc-blende structure were successfully synthesized via a phosphine-free synthetic route by controlling the doping temperature. The products were Mn:CdSe d-dots at 160 °C, but undoped CdSe nanocrystals at 200 °C. The rapid ejection process of Mn ions from the host CdSe lattice at above 180 °C could be observed by monitoring the changes of spectra characterizations of the reaction products. A possible mechanism that Mn ions were rapidly ejected from the host CdSe lattice under the high temperature was proposed. Combining with TEM and spectral results of the resulting nanocrystals, the mechanism was further confirmed powerfully by the annealing for the presynthesized and purified Mn:CdSe nanocrystals