Theoretical and experimental investigation of doping M in ZnSe (M = Cd,Mn, Ag,Cu) clusters: optical and bonding characteristics

The optical and bonding characteristics of doping ZnSe quantum dots (QDs) were investigated. Cd‐, Mn‐, Ag‐ and Cu‐doped ZnSe were synthesized in aqueous solution. Theoretically, the intensity of the Cd–Se bond was similar to that of the Zn–Se bond, which illustrates that Cd can be doped into ZnSe materials at any ratio. We found that Mn–Se bonding was stronger than Zn–Se bonding. Ag‐doped ZnSe nanoclusters show the same bonding and configuration as Cu‐doped ZnSe. Moreover, Cd can be doped into ZnSe using both the substitution‐ and vacancy‐doping method. For Mn‐doped ZnSe clusters, small amounts of Mn impurity lead to stronger bonding with Se, but larger amounts of Mn impurity led to the formation of a Mn–Mn metal bond. The theoretical results show that it is difficult to form a vacancy‐doping cluster for Mn‐doped ZnSe materials. In experiments, the absorption and photoluminescence (PL) spectral wavelengths of Mn‐doped ZnSe nanocrystals were the same as those of pure ZnSe nanocrystals, showing that the Mn impurity is not doped into ZnSe nanocrystals. Ag‐ and Cu‐doped ZnSe nanocrystals have the same PL characteristics. The doping of an impurity is related to the solubility product, and not the bonding intensity. Copyright © 2015 John Wiley & Sons, Ltd.