High efficiency small molecule tandem photovoltaic devices

Patent metadata

Field	Value
Publication number	US-11094902-B2
Application number	US-201415030152-A
Country	US
Kind code	B2
Filing date	Oct 27, 2014
Priority date	Oct 25, 2013
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

A high efficiency small molecule tandem solar cell is disclosed. The tandem cell may include a first subcell comprising a first photoactive region and a second subcell comprising a second photoactive region. The first and second photoactive regions are designed to minimize spectral overlap and maximize photocurrent. The device may further include an interconnecting layer, disposed between the first subcell and the second subcell, that is at least substantially transparent.

First claim

What is claimed is:

1. A tandem photovoltaic device comprising:
a first subcell comprising a first photoactive region;
a second subcell comprising a second photoactive region; and
a separating layer between the first subcell and the second subcell, wherein the separating layer comprises an interconnecting layer comprising bathophenanthroline (BPhen):C 60 ;
wherein:
the first photoactive region comprises a first donor material and a first acceptor material forming a first donor-acceptor heterojunction;
the second photoactive region comprises a second donor material and a second acceptor material forming a second donor-acceptor heterojunction;
the first donor material comprises 2-((7-(5-(dip-tolylamino)thiophen-2-yl)benzo[c] [1,2,5]thiadiazol-4-yl)methylene)malononitrile (DTDCTB) or a derivative thereof;
the first acceptor material comprises C 60 ;
the second donor material comprises dibenzo([f,f′]-4,4′,7,7′-tetraphenyl)diindeno[1,2,3-cd:1′,2′,3′-lm]perylene (DBP) or a derivative thereof;
the second acceptor material comprises C 70 ; and
the first subcell is the front subcell and the second subcell is the back subcell, such that incident light enters the device through the first subcell and light that is not absorbed by the first subcell is passed to the second subcell.

2. The tandem photovoltaic device of claim 1 , wherein the first donor-acceptor heterojunction is chosen from a mixed heterojunction and a hybrid planar-mixed heterojunction.

3. The tandem photovoltaic device of claim 1 , wherein the second donor-acceptor heterojunction is chosen from a mixed heterojunction and a hybrid planar-mixed heterojunction.

4. The tandem photovoltaic device of claim 1 , wherein the first and second donor-acceptor heterojunctions are chosen from mixed heterojunctions and hybrid planar-mixed heterojunctions.

5. The tandem photovoltaic device of claim 1 , wherein the second donor material comprises DBP.

6. The tandem photovoltaic device of claim 5 , wherein the first donor material comprises DTDCTB.

7. The tandem photovoltaic device of claim 1 , wherein the separating layer further comprises a charge recombination layer.

8. The tandem photovoltaic device of claim 7 , wherein the charge recombination layer comprises a material chosen from Al, Ag, Li, LiF, Sn, and Ti.

9. The tandem photovoltaic device of claim 7 further comprising a charge collecting layer between the separating layer and one of the first and second photoactive regions, wherein the charge collecting layer comprises a metal oxide.

10. The tandem photovoltaic device of claim 9 , wherein the metal oxide is chosen from MoO 3 , V 2 O 5 , ZnO, and TiO 2 .

11. The tandem photovoltaic device of claim 1 , wherein the first donor material comprises DTDCTB.

Assignees

• Univ Michigan Regents

Inventors

• Forrest Stephen R
• Che Xiaozhou
• Xiao Xin

Classifications

• H10K30/353

  comprising blocking layers, e.g. exciton blocking layers · CPC title

• H10K30/211

  comprising multiple junctions, e.g. double heterojunctions · CPC title

• H10K30/20

  comprising organic-organic junctions, e.g. donor-acceptor junctions · CPC title

• H10K85/624 Primary

  containing six or more rings · CPC title

• Y02E10/549

  Organic PV cells · CPC title