The luminescence characteristics of Zn1-xHoxSe QDs synthesized via a polyol-assisted microwave technique for light emitting device applications

Highly luminescent Zn1-xHoxSe (0 < x < 0.05) QDs were prepared using the polyol-assisted microwave approach for light-emitting device applications. The influence of the holmium atoms (Ho) on the structure and morphology of the ZnSe nanocrystals was emphasized using X-ray diffraction (XRD) and transmission electron microscope (TEM) measurements. The inclusion of the Ho-atoms in the ZnSe nanocrystals increases the particle size while preserving the cubic phase of the ZnSe nanocrystals. The inclusion of the Ho-atoms in the Zn-sites of the ZnSe nanocrystals decreases the optical bandgap. The photoluminescence measurements revealed that the introduction of the Ho-atoms in the Zn-sites of the ZnSe nanocrystals results in a redshift of the emission peaks and the increase of the luminescence intensity. Furthermore, the bandwidth of the emitted light is decreased due to the incorporation of the Ho-atoms in the ZnSe nanocrystals. The increase of the Ho-atoms concentration led to a decrease of the Stokes shift and an increase of the quantum yield reached 81%. Therefore, the developed synthetic recipe and the partial replacement of the Zn-atoms by Ho-atoms in the ZnSe crystal structure may open a new door to use the Zn1-xHoxSe QDs for LEDs application.

Automated summary

Highly luminescent Zn1-xHoxSe (0 < x < 0.05) QDs were prepared by incorporating holmium atoms into the ZnSe nanocrystals. The introduction of holmium atoms increased the particle size, decreased the optical bandgap, and resulted in a redshift of the emission peaks and increased luminescence intensity. Furthermore, the bandwidth of the emitted light was reduced and the quantum yield increased.