General synthesis and white light emission of diluted magnetic semiconductor nanowires using single-source precursors

Because of the fundamental properties and possible applications in spin-based electronics and photonics, diluted magnetic semiconductor nanowires are actively pursued. Here we report a general and facile solution synthetic strategy to prepare colloidal diluted magnetic semiconductor nanowires through solution-liquid-solid (SLS) doping approach using single-source precursors. On the basis of this strategy, transition metal ions such as Mn and Eu doped CdS nanowires were successfully synthesized and characterized. The material characterizations demonstrated that the doping process is nucleation controlled. We further investigated the Mn doping effects on nanowire growth as well as their photoluminescence properties. The Mn doped CdS nanowires exhibit photoluminescence emission related to the excitonic magnetic polaron in CdS, single Mn²⁺ ion and Mn-S-Mn centers as well as trap states, evidenced by the time-resolved photoluminescence spectra and magnetic measurements. With the increase of Mn precursor that used in the doping process, the Mn ²⁺ related emission becomes more pronounced. By tuning the doping concentration, white emissive doped CdS nanowires were achieved.