Cadmium-free quantum dot nanoparticles

Patent metadata

Field	Value
Publication number	US-9853190-B2
Application number	US-201414579237-A
Country	US
Kind code	B2
Filing date	Dec 22, 2014
Priority date	Jan 6, 2014
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

Quantum dot semiconductor nanoparticle compositions that incorporate ions such as zinc, aluminum, calcium, or magnesium into the quantum dot core have been found to be more stable to Ostwald ripening. A core-shell quantum dot may have a core of a semiconductor material that includes indium, magnesium, and phosphorus ions. Ions such as zinc, calcium, and/or aluminum may be included in addition to, or in place of, magnesium. The core may further include other ions, such as selenium, and/or sulfur. The core may be coated with one (or more) shells of semiconductor material. Example shell semiconductor materials include semiconductors containing zinc, sulfur, selenium, iron and/or oxygen ions.

First claim

What is claimed is:

1. A method of making a semiconductor nanoparticle, comprising:
combining an indium source precursor and at least two metal source precursors selected from the group consisting of magnesium source precursors, aluminum source precursors, calcium source precursors and zinc source precursors in a solvent at a first temperature to form a mixture;
adding a molecular seeding compound to the mixture at the first temperature to form a molecular seeding compound-containing mixture;
adding a phosphorus source precursor to the molecular seeding compound-containing mixture to form a semiconductor nanoparticle precursor mixture;
heating the semiconductor nanoparticle precursor mixture to a second temperature; and
annealing the semiconductor nanoparticle precursor mixture at the second temperature.

2. The method recited in claim 1 , wherein the first temperature is 100° C.

3. The method recited in claim 1 , wherein the second temperature is from 195° C. to 250° C.

4. The method recited in claim 1 , wherein the ratio of the indium to the at least two additional metals is about 3:1 to about 4:1.

5. The method recited in claim 1 , wherein the molecular seeding compound is zinc sulfide.

Assignees

• Nanoco Technologies Ltd

Inventors

• Glarvey Paul Anthony
• Harris James
• Daniels Steven
• Pickett Nigel
• Narayanaswamy Arun

Classifications

• B22F1/16

  Metallic particles coated with a non-metal (coated with lubricating or binding agents or with organic material B22F1/10) · CPC title

• B22F1/054

  Nanosized particles · CPC title

• C09K11/64

  containing aluminium · CPC title

• C01P2004/64

  Nanometer sized, i.e. from 1-100 nanometer · CPC title

• C09K11/71 Primary

  also containing alkaline earth metals · CPC title