Large-Scale Synthesis of InPZnS Alloy Quantum Dots with Dodecanethiol as a Composition Controller

Abstract

A method for the large-scale synthesis of InPZnS alloy QDs was developed, which tune the optical properties by controlling the dodecanethiol to palmitic acid ratio. The control of the surfactant ratio resulted in the change of alloy composition. The absorption and emission peaks showed a blue shift as the amount of DDT increased, which implied the increase of ZnS contents. The alloy structure was confirmed with TEM, elemental analysis, XRD, and XPS; particularly, P 2p peaks for In−P and InP−S bonds in XPS analysis could give clear evidence. The alloy QDs were overcoated with a ZnS shell, and the quantum yields (QYs) were in the range of 20− 45% for all wavelengths. Finally, a cadmium-free QD yield in a single reaction was determined to be 2.74 g. SECTION: Nanoparticles and Nanostructures

Tuning the Lattice Parameter of InxZnyP for Highly Luminescent Lattice-Matched Core/Shell Quantum Dots

“…InP-based QDs are among the most investigated nontoxic Cd-free systems, owing to their comparable emission range. [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] However, in terms of PL QY and PL stability they cannot yet compete with Cd-based QDs.…”

“…Although the addition of Zn to the synthesis of InP nanocrystals has become common practice in the last years, [11][12][13][14][15][16][17][21][22][23][24][25] very little has been reported on the actual role of the Zn. The few reports on this topic have focused on the effect on the optical properties, but structural aspects were not investigated.…”

Review: Down Conversion Materials for Solid‐State Lighting

“…200 InP shells were grown on ZnSe by slow addition of a mixture of In-tributyl phosphine and P (SiMe 3 ) 3 in octadecene to a degassed solution of ZnSe QDs, octadecene, and palmitic acid. 202 Currently, efforts are being made to scale up the reaction volumes 192,193 and to better understand the experimental parameters that most affect the final product. 202 Currently, efforts are being made to scale up the reaction volumes 192,193 and to better understand the experimental parameters that most affect the final product.…”

“…InP/ZnS core/shell QDs (a Type I system) show emission maxima from 500 to 630 nm with QYs as high as 42% 192,193 and as high as 70%, 194 depending on the details of the synthesis. InP/GaP/ZnS QDs with extremely thin GaP layers 195 have emission from 500 to 600 nm, show much improved thermal stability at 150°C (in comparison to InP/ZnS), and exhibit QYs as high as 85%.…”

Synthesis and properties of colloidal indium phosphide quantum dots

“…Excess indium carboxylate was of importance for not only rapid nucleation and stable growth, but also for the formation of a surface enriched with indium, which ensured the binding of the necessary amount of ligands on the surface. Mean while, a procedure for the synthesis of mixed InPZnS QDs was proposed in [64]. According to this proce dure, a zinc source (zinc acetate) and a dodecaneth iol-palmitic acid (PA) mixture were present in a solu tion of an indium precursor (indium acetate), while (TMS) 3 P solution in octadecene was used as a phos phorus precursor.…”