Facile synthesis of monodisperse ZnS capped CdS nanocrystals exhibiting efficient blue emission

Abstract

A new method for the capping of colloidal CdS nanocrystals with ZnS shells is presented. A combination of the monomolecular precursor zinc ethylxanthate (Zn(ex) 2 ) and zinc stearate was used to replace hazardous organometallic reagents usually applied in this procedure, i.e. bis(trimethylsilyl) sulfide and diethylzinc. Its simple preparation, air-stability and low decomposition temperature of 150°C make Zn(ex) 2 a very suitable source for the ZnS shell growth. With this precursor, highly luminescent CdS/ ZnS core/shell nanocrystals (Q.Y. 35-45%), exhibiting narrow emission linewidths of 15-18 nm (FWHM) in the blue spectral region, can reproducibly be obtained.

SAXS exploration of the synthesis of ultra monodisperse silica nanoparticles and quantitative nucleation growth modeling

“…Such nanoparticles, especially when they are monodisperse, are very useful not only for theoretical studies but also for many practical applications (quantum dots, fluorescent nanoparticles, nanoparticle assemblies) [4][5][6][7][8][9][10][11][12].…”

Multicolored silica coated CdSe core/shell quantum dots

“…It is well known that ZnS is the best protecting shell for CdSe QDs because of the considerable differences in the values of the band gap energies 16 . Low-temperature (120 o C) synthesis was used to cover the CdSe cores directly with ZnS shells, using OA and OLA as stabilizers.…”

Degradation Studies of Colloidal Quantum Dot Light-Emitting Diodes

“…The core/shell CdSe/ZnS QDs used in this work were synthesized with an organometallic approach modified from that reported in [8] Structure of the QD LEDs /PSS on UV-ozone treated ITO substrates, over which Poly-TPD was then solution cast from the chlorobenzene as the hole transport layer (HTL). A QD layer was then spin coated from the toluene solution as the emission layer (EML).…”