Synthesis of InP quantum dots in dodecylamine from phosphine and indium(III) chloride

Vinokurov²,

Lebedev³

et al. 2016

Nano Online

Zinc-doped InP(Zn) colloidal quantum dots (QDs) with narrow size distribution and low defect concentration were grown for the first time via a novel phosphine synthetic route and over a wide range of Zn doping. We report the influence of Zn on the optical properties of the obtained quantum dots. We propose a mechanism for the introduction of Zn in the QDs and show that the incorporation of Zn atoms into the InP lattice leads to the formation of Zn acceptor levels and a luminescence tail in the red region of the spectra. Using photochemical etching with HF, we confirmed that the Zn dopant atoms are situated inside the InP nanoparticles. Moreover, doping with Zn is accompanied with the coverage of the QDs by a zinc shell. During the synthesis Zn myristate covers the QD nucleus and inhibits the particle growth. At the same time the zinc shell leads to an increase of the luminescence quantum yield through the reduction of phosphorous dangling bonds. A scenario for the growth of the colloidal InP(Zn) QDs was proposed and discussed.

Section: Introductionmentioning

confidence: 99%

Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

Vinokurov²,

Lebedev³

et al. 2016

Nano Online

“…There are several synthetic approaches to obtain InP QDs [6–10]. One of the most commonly used methods nowadays includes the thermal decomposition of sililphosphides [11].…”

Section: Introductionmentioning

confidence: 99%

“…This is a quite complicated method because of the reactivity and inflammability of such substances. Recently, we developed the simplest way to date to produce such material by using phosphine (PH 3 ) as a source of phosphorus [6] and indium carboxilates as a source of indium with various carbonic acids as surfactants in nonpolar solvents. This method leads to relatively narrow particle size distributions with mean diameters of about 1–7 nm, a high crystallinity of the nanoparticles and the temporal stability of the optical properties.…”

Section: Introductionmentioning

confidence: 99%

Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

Beilstein J. Nanotechnol.

Vinokurov²,

Lebedev³

et al. 2015

SummaryZinc-doped InP(Zn) colloidal quantum dots (QDs) with narrow size distribution and low defect concentration were grown for the first time via a novel phosphine synthetic route and over a wide range of Zn doping. We report the influence of Zn on the optical properties of the obtained quantum dots. We propose a mechanism for the introduction of Zn in the QDs and show that the incorporation of Zn atoms into the InP lattice leads to the formation of Zn acceptor levels and a luminescence tail in the red region of the spectra. Using photochemical etching with HF, we confirmed that the Zn dopant atoms are situated inside the InP nanoparticles. Moreover, doping with Zn is accompanied with the coverage of the QDs by a zinc shell. During the synthesis Zn myristate covers the QD nucleus and inhibits the particle growth. At the same time the zinc shell leads to an increase of the luminescence quantum yield through the reduction of phosphorous dangling bonds. A scenario for the growth of the colloidal InP(Zn) QDs was proposed and discussed.

“…The most popular synthetic route is the reaction of an indium salt with tris(trimethylsilyl)phosphine (P(TMS) 3 ) in a solvent with a high boiling point at high temperatures [ 3 – 4 ]. This phosphorous precursor has a number of disadvantages and should be replaced with another one, for example PH 3 [ 5 – 6 ].…”

Section: Introductionmentioning

confidence: 99%

Surface processes during purification of InP quantum dots

Beilstein J. Nanotechnol.

Emelin²,

Vinokurov³

et al. 2014

SummaryRecently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)3 during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of postsynthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular.