20406-60-4Relevant articles and documents
Precursor reaction kinetics control compositional grading and size of CdSe1-: XSx nanocrystal heterostructures
Hamachi, Leslie S.,Yang, Haoran,Jen-La Plante, Ilan,Saenz, Natalie,Qian, Kevin,Campos, Michael P.,Cleveland, Gregory T.,Rreza, Iva,Oza, Aisha,Walravens, Willem,Chan, Emory M.,Hens, Zeger,Crowther, Andrew C.,Owen, Jonathan S.
, p. 6539 - 6552 (2019/07/10)
We report a method to control the composition and microstructure of CdSe1-xSx nanocrystals by the simultaneous injection of sulfide and selenide precursors into a solution of cadmium oleate and oleic acid at 240 °C. Pairs of substituted thio- and selenoureas were selected from a library of compounds with conversion reaction reactivity exponents (kE) spanning 1.3 × 10-5 s-1 to 2.0 × 10-1 s-1. Depending on the relative reactivity (kSe/kS), core/shell and alloyed architectures were obtained. Growth of a thick outer CdS shell using a syringe pump method provides gram quantities of brightly photoluminescent quantum dots (PLQY = 67 to 90%) in a single reaction vessel. Kinetics simulations predict that relative precursor reactivity ratios of less than 10 result in alloyed compositions, while larger reactivity differences lead to abrupt interfaces. CdSe1-xSx alloys (kSe/kS = 2.4) display two longitudinal optical phonon modes with composition dependent frequencies characteristic of the alloy microstructure. When one precursor is more reactive than the other, its conversion reactivity and mole fraction control the number of nuclei, the final nanocrystal size at full conversion, and the elemental composition. The utility of controlled reactivity for adjusting alloy microstructure is discussed.
Tetrakis(thione)platinum(II) complexes: Synthesis, spectroscopic characterization, crystal structures, and in vitro cytotoxicity
Mustafa, A. Zainelabdeen A.,Monim-ul-Mehboob,Jomaa,Altaf,Fettouhi,Isab,Wazeer,Stoeckli-Evans,Bhatia,Dhuna
, p. 3511 - 3524 (2015/09/28)
A new series of platinum(II) complexes based on thione ligands with general formula [Pt(thione)4]X2 (X- = Cl-, NO3-) has been synthesized and characterized using CHNS elemental analysis, infrared, 1H and 13C solution-state NMR as well as 13C and 15N solid-state NMR spectroscopy, and X-ray crystallography. The spectroscopic methods confirm the coordination of Pt(II) with thiocarbonyl groups via sulfur of the thione ligands. The X-ray structures showed a distorted square planar geometry for 1, [Pt(MeImt)4]Cl2 (MeImt = N-Methylimidazolidine-2-thione) while the hydrogen bonding interactions in 7, [Pt(iPrImt)4](NO3)2·0.6(H2O) induce a bent see-saw distortion relative to the ideal square planar geometry. The in vitro cytotoxicity studies showed that 2, [Pt(EtImt)4]Cl2 is generally the most effective, a two-fold better cytotoxic agent than cisplatin and carboplatin against MCF7 (human breast cancer).