Cu2XSnY4 nanoparticles

Patent metadata

Field	Value
Publication number	US-10756221-B2
Application number	US-201816129191-A
Country	US
Kind code	B2
Filing date	Sep 12, 2018
Priority date	Mar 15, 2013
Publication date	Aug 25, 2020
Grant date	Aug 25, 2020

Abstract

Materials and methods for preparing Cu2XSnY4 nanoparticles, wherein X is Zn, Cd, Hg, Ni, Co, Mn or Fe and Y is S or Se, (CXTY) are disclosed herein. The nanoparticles can be used to make layers for use in thin film photovoltaic (PV) cells. The CXTY materials are prepared by a colloidal synthesis in the presence of labile organo-chalcogens. The organo-chalcogens serves as both a chalcogen source for the nanoparticles and as a capping ligand for the nanoparticles.

First claim

What is claimed is:

1. A method for preparing an absorber layer for a photovoltaic (PV) device, the method comprising:
dissolving or dispersing a population of nanoparticles in a solvent to form a nanoparticle ink, each nanoparticle comprising:
a semiconductor nanocrystal having an outer surface, the semiconductor nanocrystal having the formula Cu 2 XSnY 4 , where X is Cd, Hg, Ni, Co, Mn, or Fe and Y is S or Se; and
a surface coating on the outer surface of the semiconductor nanocrystal and consisting of labile organo-chalcogen ligands;

depositing the nanoparticle ink on a substrate to form a nanoparticle film;
annealing the substrate and nanoparticle film at a first temperature for a first time interval; and
annealing the substrate and nanoparticle film at a second temperature for a second time interval,
wherein the second temperature is higher than the first temperature.

2. The method of claim 1 , wherein the solvent is a non-polar solvent.

3. The method of claim 1 , wherein the nanoparticle ink is deposited on the substrate by any one of spin-coating, slit-coating, drop-casting, doctor blading, and inkjet printing.

4. The method of claim 1 , wherein the first temperature is between 260 and 350° C.

5. The method of claim 1 , wherein the first time interval is between 3 and 10 minutes.

6. The method of claim 1 , wherein the second temperature is between 350 and 440° C.

7. The method of claim 1 , wherein the second time interval is between 3 and 10 minutes.

8. The method of claim 1 , further comprising annealing at a third temperature for a third time interval, wherein the third temperature is higher than the second temperature.

9. The method of claim 8 , wherein the third temperature is between 500 and 600° C.

10. The method of claim 8 , wherein the third time interval is between 30 minutes and 3 hours.

11. The method of claim 8 , wherein annealing at the third temperature for the third time interval is conducted under a chalcogen-rich atmosphere.

12. The method of claim 1 , wherein the population of nanoparticles further comprises copper selenide.

Assignees

• Nanoco Technologies Ltd

Inventors

• Gresty Nathalie
• Harris James
• Masala Ombretta
• Pickett Nigel
• Wylde Laura
• Newman Christopher

Classifications

• H10F71/00

  Manufacture or treatment of devices covered by this subclass (patterning processes to connect thin photovoltaic cells in integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/33; manufacture or treatment of encapsulations or containers for integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/80; manufacture or treatment of integrated devices, or assemblies of multiple devices, comprising at least one element in which radiation controls the flow of current H10F39/00) · CPC title

• H10F77/12 Primary

  Active materials · CPC title

• Y02E10/52

  PV systems with concentrators · CPC title

• B82Y30/00 Primary

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• C01G19/006

  Compounds containing tin, with or without oxygen or hydrogen, and containing two or more other elements · CPC title