Mixed cation perovskite

Patent metadata

Field	Value
Publication number	US-10535828-B2
Application number	US-201615779174-A
Country	US
Kind code	B2
Filing date	Nov 25, 2016
Priority date	Nov 27, 2015
Publication date	Jan 14, 2020
Grant date	Jan 14, 2020

Abstract

The present invention relates to a crystalline compound comprising: (i) Cs+ (caesium); (ii) (H2N—C(H)—NH2)+ (formamidinium); (iii) one or more metal or metalloid dications [B]; and (iv) two or more different halide anions [X]. The invention also relates to a semiconductor device comprising a semiconducting material, which semiconducting material comprises the crystalline compound. The invention also relates to a process for producing a layer of the crystalline compound.

First claim

The invention claimed is:

1. A crystalline compound which is a perovskite of formula:
Cs 0.17 (H 2 N—C(H)═NH 2 ) 0.83 PbBr 3y I 3(1-y) ,

wherein y is from 0.01 to 0.99.

2. A crystalline compound according to claim 1 , wherein
y is from 0.01 to 0.70 or
y is from 0.20 to 0.60.

3. A crystalline compound according to claim 1 , wherein
y is from 0.30 to 0.50.

4. A crystalline compound according to claim 1 , wherein the crystalline compound is Cs 0.17 (H 2 N—C(H)═NH 2 ) 0.83 Pb(Br 0.4 I 0.6 ) 3 .

5. A crystalline compound according to claim 1 , wherein the crystalline compound is Cs 0.175 (H 2 N—C(H)═NH 2 ) 0.825 Pb(Br 0.4 I 0.6 ) 3 .

6. A crystalline compound according to claim 1 , wherein the crystalline compound has a band gap of from 1.5 to 2.0 eV.

7. A crystalline compound according to claim 1 , wherein the crystalline compound is in the form of particles comprising the crystalline compound.

8. A semiconducting material comprising a crystalline compound which is a perovskite of formula Cs 0.17 N(H 2 N—C(H)═NH 2 ) 0.83 PbBr 3y I 3(1-y) , wherein y is from 0.01 to 0.99.

9. A semiconducting material according to claim 8 , wherein the semiconducting material comprises greater than or equal to 80% by weight of the crystalline compound.

10. A semiconductor device comprising a semiconducting material, which semiconducting material comprises a crystalline compound, which crystalline compound comprises a perovskite of formula Cs 0.17 (H 2 N—C(H)═NH 2 ) 0.83 PbBr 3y I 3(1-y) , wherein y is from 0.01 to 0.99.

11. A semiconductor device according to claim 10 , wherein the crystalline compound is a perovskite of formula wherein
y is from 0.01 to 0.70 or
y is from 0.20 to 0.60.

12. A semiconductor device according to claim 10 , wherein the semiconductor device is an optoelectronic device, preferably wherein the semiconductor device is a photovoltaic device, a photodetector or a light-emitting device, more preferably wherein the semiconductor device is a photovoltaic device.

13. A semiconductor device according to claim 10 , which semiconductor device comprises a layer of said semiconducting material, preferably wherein the layer of said semiconducting material has a thickness of from 5 nm to 10000 nm.

14. A semiconductor device according to claim 10 , which semiconductor device comprises:
an n-type region comprising at least one n-type layer;
a p-type region comprising at least one p-type layer; and,
disposed between the n-type region and the p-type region: a layer of said semiconducting material.

15. A semiconductor device according to claim 10 , which semiconductor device is a tandem photovoltaic device and further comprises a layer of a second semiconductor material wherein the band gap of the second semiconductor material is lower than the band gap of the semiconductor material comprising the crystalline compound, preferably wherein the second semiconductor material comprises silicon, a perovskite, copper indium selenide (CIS), copper indium gallium diselenide (CIGS), CdTe, PbS or PbSe.

16. A semiconductor device which is a tandem photovoltaic device according to claim 15 , wherein the tandem photovoltaic device comprises:
(i) a layer of silicon;
(ii) disposed on the layer of silicon, a layer of a transparent conducting oxide;
(iii) disposed on the layer of a transparent conducting oxide, an n-type region comprising at least one n-type layer;
(iv) disposed on the n-type region, a layer of said semiconducting material;
(v) disposed on the layer of said semiconducting material, a p-type region comprising at least one p-type layer; and
(vi) disposed on the p-type region, a layer of an electrode material.

17. A semiconductor device according to claim 10 , which device comprises
a layer of a transparent conducting oxide;
disposed on the layer of the transparent conducting oxide, a layer of an n-type metal oxide;
disposed on the layer of the n-type metal oxide, a layer of said crystalline compound; and
disposed on the layer of the crystalline compound, a layer of an electrode material.

18. A process for producing a layer of a crystalline compound, which crystalline compound comprises a perovskite of formula Cs 0.17 (H 2 N—C(H)═NH 2 ) 0.83 PbBr 3y I 3(1-y) , wherein y is from 0.01 to 0.99,
which process comprises:
(a) disposing on a substrate a precursor composition comprising:
CsBr and/or CsI′;
(H 2 N—C(H)═NH 2 )Br and/or (H 2 N—C(H)═NH 2 )I′;
PbBr 2 and/or PbI′ 2 .

19. A process according to claim 18 , wherein disposing on a substrate a precursor composition comprises:
(Ai) exposing the substrate to one or more vapours, which one or more vapours comprise said precursor composition; and
(Aii) allowing deposition of the one or more vapours onto the substrate to produce a layer of the crystalline compound thereon;
or
(Bi) disposing the precursor composition and one or more solvents on the substrate; and
(Bii) removing the one or more solvents to produce on the substrate a layer of crystalline compound.

20. A process according to claim 18 , wherein the crystalline compound is a perovskite of formula wherein
y is from 0.01 to 0.70 or
y is from 0.20 to 0.60.

21. A process according to claim 18 , wherein the precursor composition comprises:
CsI and/or CsBr;
(H 2 N—C(H)═NH 2 )I and/or (H 2 N—C(H)═NH 2 )Br;
PbI 2 ;
PbBr 2 ; and
a polar aprotic solvent.

22. A process for producing a semiconductor device, which process comprises a process for producing a layer of a crystalline compound as defined in claim 18 .

Assignees

• Univ Oxford Innovation Ltd

Inventors

• Saliba Michael
• Mcmeekin David
• Snaith Henry James
• Wenger Bernard

Classifications

• C07F7/24

  Lead compounds · CPC title

• H01L51/447 Primary

  Electricity · mapped topic

• H01L51/0032

  Electricity · mapped topic

• H01L51/0008

  Electricity · mapped topic

• H01L51/4226

  Electricity · mapped topic