Tellurium Precursor for Nanocrystal Synthesis: Tris(dimethylamino)phosphine Telluride

Abstract

Preparations of CdTe quantum platelets, magic-size (CdTe) 13 nanoclusters, and CdTe quantum wires are described using (Me 2 N) 3 PTe (with (Me 2 N) 3 P) as a Te precursor. The (Me 2 N) 3 PTe/(Me 2 N) 3 P precursor mixture is shown to be more reactive than mixtures of trialkylphosphine tellurides and the corresponding trialkylphosphines, R 3 PTe/R 3 P, which are commonly employed in nanocrystal syntheses. For syntheses conducted in primary amine solvents, (Me 2 N) 3 PTe and (Me 2 N) 3 P undergo a transamination reaction, affording (Me 2 N) x (RHN) 3−x PTe and (Me 2 N) x (RHN) 3−x P (R = n-octyl or oleyl). The transaminated (Me 2 N) x (RHN) 3−x PTe derivatives are shown to be the likely Te precursors under those conditions. The enhanced reactivities of the tris(amino)phosphine tellurides are ascribed to increased nucleophilicity due to the amino-N lone pairs.

Absorption Features of CdTe Nanoclusters: Aspect Ratio Dependency of the Singlet/Doublet from First-Principles Calculations

“…The size mentioned here is proposed to be the size of all three dimensions, including the effect of shape and volume . Abundant explorations have been focused on the shape-dependent optical properties for semiconductor nanoparticles, like CdSe, CdTe, CdS, and PbS with dotted, rod, and wired structures. − In recent years, several types of group II–VI magic-size clusters (MSCs) have been observed in experiments. − MSCs are a kind of special clusters with a defined number of atoms and chemical structures, together with high stability and special optical properties . When MSCs are synthesized experimentally, sharp absorption peaks can be detected, with fixed positions in the UV–vis absorption spectra.…”

“…When MSCs are synthesized experimentally, sharp absorption peaks can be detected, with fixed positions in the UV–vis absorption spectra. CdTe MSCs with singlet or doublet absorption features have been found, such as singlet MSC-371 (denoted as sMSC-371), sMSC-448, doublet MSC-371 (denoted as dMSC-371), and dMSC-488. − The words “singlet” and “doublet” refer to absorption features here and have been used to describe the shape of the absorption peak in many works. ,− , CdTe sMSC-371 and dMSC-371, which exhibit diverse absorption features but the same first absorption peak position, have attracted our attention. Although the transmission electron microscopy images of dMSC-371 and sMSC-371 have been reported experimentally, , their detailed atomic structures have not been pointed out.…”

“…CdTe MSCs with singlet or doublet absorption features have been found, such as singlet MSC-371 (denoted as sMSC-371), sMSC-448, doublet MSC-371 (denoted as dMSC-371), and dMSC-488. − The words “singlet” and “doublet” refer to absorption features here and have been used to describe the shape of the absorption peak in many works. ,− , CdTe sMSC-371 and dMSC-371, which exhibit diverse absorption features but the same first absorption peak position, have attracted our attention. Although the transmission electron microscopy images of dMSC-371 and sMSC-371 have been reported experimentally, , their detailed atomic structures have not been pointed out. There may exist some correlations in their morphologies, for the transformations between these two MSCs were observed experimentally, and they were proposed to be a pair of isomers. , Thus, it is necessary to establish a theoretical research on the shape-determined singlet and doublet absorptions.…”

“…14,[17][18][19]26 CdTe sMSC-371 and dMSC-371, which exhibit diverse absorption features but the same first absorption peak position, have attracted our attention. Although the transmission electron microscopy images of dMSC-371 and sMSC-371 have been reported experimentally, 17,20 their detailed atomic structures have not been pointed out. There may exist some correlations in their morphologies, for the transformations between these two MSCs were observed experimentally, and they were proposed to be a pair of isomers.…”

Synthesis of Atomically Thin CdTe Nanoplatelets by Using Polytelluride Tellurium Precursors

“…investigated the colloidal synthesis of wurtzite CdTe NPLs by using tris(dimethylamino)phosphine telluride ((Me2N)3PTe) as telluride precursor. [20] Dubertret et al reported the colloidal synthesis of zinc-blende CdTe NPLs using cadmium propionate (Cd(prop)2) or cadmium acetate (Cd(OA)2) as the cadmium precursor and TOP-Te as the tellurium precursor. [21] The lateral size and shape of these zinc-blende CdTe NPLs can be further controlled by changing the hot-injection temperature or the molar ratio of oleic acid to the cadmium precursor with short-chain carboxylate groups.…”