Abstract
Wir zeigen, ein Verfahren zur Synthese von Mehrkomponenten-Nanostrukturen, bestehend aus CdS und CdSe mit Stab und tetrapod Morphologien. Ein ausgesät Synthesestrategie eingesetzt wird, bei dem kugelförmige Samen von CdSe zunächst mit einem Heißinjektionstechnik hergestellt. Durch Steuern der Kristallstruktur des Samens entweder Wurtzit-oder Zinkblende, die anschließende Heißinjektions Wachstum von CdS aus den Samen führt entweder zu einem stabförmigen oder tetrapodförmigen Nanokristall betragen. Die Phase und Morphologie der Nanokristalle werden durch Röntgenbeugung und Transmissionselektronenmikroskopie bestätigt, die zeigen, dass die Nanokristalle sind phasenrein und haben eine einheitliche Morphologie. Der Extinktionskoeffizient und die Quantenausbeute der Nanokristalle werden mit UV-VIS-Absorptionsspektroskopie und Photolumineszenz-Spektroskopie ermittelt. Die Stäbe und tetrapods Ausstellungs Extinktionskoeffizienten und Quantenausbeuten, die höher ist als die der bloßen sindSamen. Dieses Verfahren zeigt die genaue Anordnung der Materialien, die im Nanometerbereich durch Verwendung einer geimpften Syntheseverfahren erreicht werden können.
Materials
Name | Company | Catalog Number | Comments |
Sodium hydroxide, 98% | Fisher | BP359 | |
Myristic acid, 99% | Sigma Aldrich | M3128 | |
Methanol, 99.8% | Fisher | A412 | |
Cadmium nitrate tetrahydrate, 99% | Sigma Aldrich | 20911 | Highly toxic |
Cadmium oxide (CdO), 99.99% | Sigma Aldrich | 202894 | Highly toxic |
1-Octadecene (ODE), 90% | Sigma Aldrich | O806 | Technical grade |
Selenium (Se), 100 mesh, 99.99% | Sigma Aldrich | 229865 | |
Tri-n-octylphosphine (TOP), 97% | Strem | 15-6655 | Air sensitive |
Sulfur (S), 99.9995% | Alfa Aesar | 10343 | |
Trioctylphosphine oxide (TOPO), 99% | Strem | 15-6661 | |
N-Octadecylphosphonic acid (ODPA), 99% | PCI Synthesis | 104224 | |
Methanol, anhydrous, 99.8% | Sigma Aldrich | 322415 | |
Toluene, anhydrous, 99.8% | Sigma Aldrich | 244511 | |
Chloroform, anhydrous, 99% | Sigma Aldrich | 288306 | |
Acetone, 99.9% | Fisher | A949 | Dried over 4Å sieves |
Hexane, anhydrous, 95% | Sigma Aldrich | 296090 | |
2-Propanol, anhydrous, 99.5% | Sigma Aldrich | 278475 | |
Selenium dioxide, 99.999% | Sigma Aldrich | 204315 | |
Oleic acid, 90% | Sigma Aldrich | 364525 | Technical grade |
Oleylamine, 70% | Sigma Aldrich | O7805 | Technical grade |
Propylphosphonic acid (PPA), 95% | Sigma Aldrich | 305685 | |
Ethanol, anhydrous, 99.5% | Sigma Aldrich | 459836 | |
Octylamine, 99% | Sigma Aldrich | O5802 |
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