- Complete the QD synthesis begun yesterday
- Continue precipitation of JCS 1 and JCS 2
- Begin precipitation of JCS 3
- Create 20 mM sodium sulfide solution
- .024018 g of Sodium Sulfide (MW=240.18) needed for 5 mL
- Used .1373 g of Sodium Sulfide used (in 5 mL) because the sample is contaminated with excess water
- Add 4 mL of 20 mM sodium sulfide solution to reaction
- Allowed the mixture to stir vigorously for 15 minutes
- Poured contents (minus the stir bar) into a darkened falcon tube and filled with 200 proof ethanol to the 50 mL mark. The falcon tube was left in the freezer to begin precipitation.
- total synthesis time: 13 hrs (including 15 minutes for Sodium Sulfide addition)
- Removed 1 mL aliquot from JCS 3 (before adding ethanol) for future testing with UVVIS and Fluorescence
Precipitation of JCS 1 and 2
- Falcon tubes spun at 4000 RPM for 15 minutes
- Solvent was decanted and stored while the dark precipitate was re-suspended in ~15 mL of distilled water.
- Solutions were stored in the dark at room temp for future analysis with UVVIS and fluorescence.
- JCS 1 remained mostly clear with minimal dark precipitate, as it was before it was spun.
- JCS 2 remained darkened brown. After spinning some precipitate was visible
- Eleni and I feel that the next step is to try centrifugation at very high speeds, which was necessary with some of the Mg:ZnS quantum dots we created last semester.