Aqueous synthesis of highly luminescent ternary alloyed Mn-doped ZnSeS quantum dots capped with 2-mercaptopropionic acid

Highly photoluminescent and water dispersible ternary alloyed Mn-doped ZnSeS core/shell Mn:ZnSeS/ZnS quantum dots (QDs) with pure dopant emission were synthesized through a simple aqueous route using thiolactic acid (2-MPA) as capping ligand. Transmission electron microscopy X-ray diffraction show that Mn:ZnSeS nanocrystals are of spherical shape, diameter 2.4 nm cubic zinc blende structure. With the overcoating ZnS shell, particle size increases to 3.7 nm, which confirms epitaxial growth shell on cores. The photoluminescence (PL) yield depends Mn loading reaches 22% for cores doped 10% 41% after at surface due effective elimination surface-trap states. QDs exhibit also long PL lifetimes (up 681 ?s) indicating originates from spin forbidden Mn2+ 4T1 ? 6A1 transition. Electron paramagnetic resonance photoelectron spectroscopy results suggest ions located interface QDs. Further, stability was investigated along their transfer in organic phase octanethiol.