I have CdSe/ZnS red emitting nanocrystals in chloroform. The PL peak of these nanocrystals is at 635 nm. When I mix the nanocrystal dispersion with nickel oxide nanoparticle powder and measure the PL again, the PL peak shifts to 655nm.
A ~20nm red shift was obtained consistently with different sized nanocrystals (cyan, green, yellow, orange and red) when mixed with nickel oxide nanoparticels.
We used a micro PL setup with a silicon CCD detector. The excitation wavelength is 473 nm and the slit width is 60 um. Attached is an example graph with two different CdSe/ZnS nanocrystals.
Original CdSe/ZnS QD are in chloroform. They were drop cast on a piece of glass and heated on a hot plate at 70 C to evaporate the solvent (chloroform). On the legend these spectra (solid lines) are named as CdSe/ ZnS on glass.
Next, the CdSe/ ZnS dispersion in chloroform is mixed (stirred fro 2 hrs) with nickel oxide nanoparticle powder and then the mixture is drop cast on to a piece of glass and heated on a hot plate at 70 C to evaporate the solvent. On the legend these spectra (dotted lines) are named as CdSe/ ZnS mixed with NiO np.
Thank you for the suggestions. I will try to repeat the experiment with chloroform as the medium.
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nanostructured Materials
- Nanoparticles