Highly Luminescent CdSe/ZnSe Core/Shell Nanocrystals of Low Size Dispersion

Nano Letters

Volumn 2, Issue 7, 2002, Pages 781-784

  Reiss, Peter ^a   Bleuse, Joël ^a   Pron, Adam ^a  

^a CEA GRENOBLE   (France)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0037603819     PISSN: 15306984     EISSN: None     Source Type: Journal    
DOI: 10.1021/nl025596y     Document Type: Article

References (28)

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20. Trioctylphosphine oxide (TOPO), trioctylphosphine (TOP), and hexadecylamine (HDA) were of the highest purity available and additionally purified by distillation. A typical synthesis of CdSe nanocrystals: 51.4 mg (0.4 mmol) of CdO is placed into a flask containing 1.15 mL of TOPO and 2.85 mL of HDA. The mixture is heated to ca. 270 °C under argon flow, then 230 μL (0.8 mmol) of dodecylphosphonic acid is added. After stabilizing the temperature of the resulting colorless solution at 250 °C, 2.5 mL of a 0.2 M solution of Se powder in TOP is quickly injected. The nanocrystal size depends on the growth time.
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24. A colloidal solution of ca. 20 mg of CdSe nanocrystals with an average diameter of 3.6 nm in 4 mL of heptane is placed in a three-neck flask under purified argon flow. After addition of 2.5 mL of TOPO and 1.5 mL of HDA, the mixture is heated to 190 °C and then kept at this temperature with the goal of a complete heptane evaporation. Zinc stearate (316 mg) is dissolved in 2.5 mL of toluene upon gentle heating (ca. 60 °C). After cooling to room temperature, the resulting 0.2 M solution is mixed with 2.5 mL of a 0.2 M solution of Se in TOP. By means of a syringe pump this mixture is injected within 1 h into the reaction flask containing the core nanocrystals at 190-200 °C. Periodically small aliquots are removed in order to monitor the shell growth. After the addition is completed the crystals are annealed at 190 °C for an additional 1-1.5 h.
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28. 4OH or NaOH or any other suitable base.