IP Library › Granted Patent US 12,672,420
Granted Patent B2
US 12,672,420 · App. 18/453,206 · Granted Jun 30, 2026

Composite materials for transport layers in perovskite solar cells

Inventors: Tomas Leijtens (Redwood City, CA); Giles Eperon (Arvada, CO); Rohit Prasanna (San Francisco, CA); Annikki Santala (Woodside, CA)
Assignee: Swift Solar Inc.
H10K30/85H10K30/57H10K85/211
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12,672,420
App. No.
18/453,206
Granted
Jun 30, 2026
Kind
B2
Abstract

Solar cell stack-ups are described in which fullerene based transport layers are blended with a metal halide such as LiF, CsF or MgF 2 . In particular, perovskite solar cell stack-ups are described in which an electron transport layer includes a metal halide and fullerene blend.

Claims (27)

1 . A solar cell comprising:

a bottom electrode;

a bottom transport layer over the bottom electrode;

a perovskite absorber layer over the bottom transport layer;

a top transport layer over the perovskite absorber layer, wherein the top transport layer includes a metal halide and fullerene blend, the metal halide is blended throughout an entire thickness of the top transport layer, and the metal halide comprises 20%-60% by volume of the top transport layer; and

a top electrode layer over the top transport layer.

2 . The solar cell of claim 1 , wherein the top transport layer is at least 5 nm thick.

3 . The solar cell of claim 1 , wherein the metal halide is uniformly blended throughout the entire thickness of the top transport layer.

4 . The solar cell of claim 1 , wherein the metal halide comprises 20%-50% by volume of the top transport layer.

5 . The solar cell of claim 1 , wherein the metal halide comprises 20%-40% by volume of the top transport layer.

6 . The solar cell of claim 1 , further comprising a wetting layer between the perovskite absorber layer and the top transport layer.

7 . The solar cell of claim 6 , wherein the wetting layer comprises LiF or fullerene.

8 . The solar cell of claim 1 , further comprising a buffer layer between the top transport layer and the top electrode layer, wherein the top transport layer is an electron transport layer (ETL).

9 . The solar cell of claim 8 , wherein the metal halide comprises Li.

10 . The solar cell of claim 8 , wherein the metal halide comprises F.

11 . The solar cell of claim 8 , wherein the buffer layer comprises a metal oxide.

12 . The solar cell of claim 11 , wherein the metal oxide is doped with aluminum.

13 . The solar cell of claim 11 , further comprising an adhesion layer between the buffer layer and the ETL.

14 . The solar cell of claim 11 , wherein the bottom transport layer, the perovskite absorber layer, and the top transport layer are part of a first subcell of a tandem solar cell, wherein the tandem solar cell further comprises a second subcell underneath the first subcell, the second subcell including a second perovskite absorber layer.

15 . The solar cell of claim 11 , wherein the bottom transport layer, the perovskite absorber layer, and the top transport layer are part of a first subcell of a tandem solar cell, wherein the tandem solar cell further comprises a second subcell underneath the first subcell, the second subcell including a p-doped silicon layer and an n-doped silicon layer.

16 . The solar cell of claim 1 , wherein:

the absorber layer is a perovskite absorber layer.

17 . The solar cell of claim 16 , wherein the metal halide comprises 20%-50% by volume of the top transport layer.

18 . The solar cell of claim 1 , wherein the metal halide comprises F.

19 . The solar cell of claim 16 , further comprising a buffer layer between the top transport layer and the top electrode layer, wherein the metal halide comprises 20%-50% by volume of the top transport layer.

20 . The solar cell of claim 19 , wherein the buffer layer comprises a metal oxide.

21 . The solar cell of claim 1 , wherein the top transport layer is a simultaneously vapor deposited layer of the metal halide and the fullerene.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 22, 2023
From: LEIJTENS, TOMAS; EPERON, GILES; PRASANNA, ROHIT; SANTALA, ANNIKKI
To: SWIFT SOLAR INC.
Reel/Frame 064663/0697 →
Continuity (2)
Continuation In Part 17821246 · Aug 22, 2022
Related Publication 20240065009A1 · Feb 22, 2024
References Cited (44)
US 10403708B2 · Ergen et al. · 2019 [cited by applicant]
US 11462688B2 · Palmstrom et al. · 2022 [cited by applicant]
US 11864399B1 · Leijtens et al. · 2024 [cited by applicant]
US 20060025311A1 · Brabec et al. · 2006 [cited by applicant]
US 20160268510A1 · Moon et al. · 2016 [cited by applicant]
US 20170125172A1 · Gong et al. · 2017 [cited by applicant]
US 20170229250A1 · Guo et al. · 2017 [cited by applicant]
US 20180075977A1 · Huang · 2018 [cited by applicant]
US 20200106019A1 · Palmstrom et al. · 2020 [cited by applicant]
US 20220093865A1 · Sugawara · 2022 [cited by applicant]
US 20220285103A1 · Shimo · 2022 [cited by applicant]
CN 112993166A · 2021 [cited by examiner]
CN 113871556A · 2021 [cited by examiner]
CN 117255575A · 2023 [cited by applicant]
KR 1020180046835A · 2018 [cited by applicant]
KR 1020230168209A · 2023 [cited by applicant]
WO WO2015085441A1 · 2015 [cited by examiner]
WO 2021010555A · 2021 [cited by applicant]
Gao (“C60:LiF Blocking Layer for Environmentally Stable Bulk Heterojunction Solar Cells”) Adv. Mater. 2010, 22, 5404-5408 (Year: 2010). [cited by examiner]
Menzel (“Field Effect Passivation in Perovskite Solar Cells by a LiF Interlayer”), Adv. Energy Mater. 2022, 12, 2201109 (Year: 2022). [cited by examiner]
English machine translation of CN 113871556 A (Year: 2024). [cited by examiner]
Liu—2013 (“Efficiency and stability enhancement of polymer solar cells using multi-stacks of C60/LiF as cathode buffer layer”) Organic Electronics 14 (2013) 469-474 (Year: 2013). [cited by examiner]
Liu—2015 (“Triple Cathode Buffer Layers Composed of PCBM, C60, and LiF for High-Performance Planar Perovskite Solar Cells”). ACS Appl. Mater. Interfaces 2015, 7, 6230-6237 (Year: 2015). [cited by examiner]
English machine translation of CN-112993166-A (Year: 2021). [cited by examiner]
Li (“Perovskite Tandem Solar Cells: From Fundamentals to Commercial Deployment”) Chem. Rev. 2020, 120, 9835-9950 (Year: 2020). [cited by examiner]
Savagatrup (“Mechanical degradation and stability of organic solar cells: Molecular and microstructural determinants”) Energy Environ. Sci., 2015, 8, 55-80 (Year: 2015). [cited by examiner]
Wu (“A Design Based on a Charge-Transfer Bilayer as an Electron Transport Layer for Improving the Performance and Stability in Planar Perovskite Solar Cells”). J. Phys. Chem. C 2018, 122, 236-244 (Year: 2018). [cited by examiner]
Zhao (“Transparent conducting C60:LiF nanocomposite thin films for organic light-emitting diodes”) Appl. Phys. Lett. 91, 103109 ( 2007) (Year: 2007). [cited by examiner]
The impact of energy alignment and interfacial recombination on the internal and external open-circuit voltage of perovskite solar cells, from the journal: Energy & Environmental Science, Issue 9, 2019, 7 pages. [cited by applicant]
C60:LiF Blocking Layer for Environmentally Stable Bulk Heterojunction Solar Cells, by Dong Gao et al., Advanced Materials, vol. 22, Issue 47, p. 5404-5408, Oct. 26, 2010. [cited by applicant]
Jay An (“Simulation and optimization studies on CsPbl3 based inorganic perovskite solar cells”) Solar Energy 221 (2021) 99-108 (Year: 2021). [cited by applicant]
English machine translation of CN 113871556 A (Year: 2023). [cited by applicant]
PCT/US2023/030799, “PCT Notification of Transmittal of the International Search Report and the Written Opinion of the International Searching Authority, or the Declaration”, mailed Jun. 21, 2024, 9 pages. [cited by applicant]
PCT/US2023/030799, “PCT Notification Concerning Transmittal of International Preliminary Report on Patentability”, mailed Mar. 6, 2025, 6 pages. [cited by applicant]
Non-Final Office Action received for U.S. Appl. No. 18/433,078, mailed on May 6, 2025, 14 pages. [cited by applicant]
Liu et al. “Efficient and stable perovskite-silicon tandem solar cells through contact displacement by MgFx”; Science 377, 302-306, Jul. 15, 2022; retrieved online https://www.science.org at U.S. Patent and Trademark Of… [cited by applicant]
Yang et al.“Stable Efficiency Exceeding 20.6% for Inverted Perovskite Solar Cells through Polymer-Optimized PCBM Electron-Transport Layers;” NANO Letters; 2019, 19, 3313-3320; DOI:10.1021/acs.nanolett.9b00936; ACS Publi… [cited by applicant]
Bai et al. “High performance inverted structure perovskite solar cells based on a PCBM:polystyrene blend electron transport layer;”J. Mater Chem A, 2015, 3, 9098-9102; DOI: 10.1039/c4ta05309e; www.rsc.org/MaterialsA; Ro… [cited by applicant]
Bai et al. “High Performance Perovskite Solar Cells based on a PCBM: polystyrene blend electron transport layer;” Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A; the Royal Society of Chemis… [cited by applicant]
Liu et al. Supplementary Materials for “Efficient and stable perovskite-silicon tandem solar cells through contact displacement by MgFx”; Science 377, 302 (2022); DOI: 10. I 126/science.abn8910; 43 pages. [cited by applicant]
PCT/US2025/014041, “PCT Notification of Transmittal of the International Search Report and the Written Opinion of the International Searching Authority, or the Declaration”, mailed May 19, 2025, 9 pages. [cited by applicant]
Wolff et al. “A universal perovskite/C60 interface modification via atomic layer deposited aluminum oxide for perovskite solar cells and perovskit⋅⋅ silicon tandems;” retrieved online: DOI:https/10.21203 rs-3364099/v1; … [cited by applicant]
Zhao et al. “Surface passivation of organometal halide perovskites by atomic layer deposition: an investigation of the mechanism of efficient inverted planar solar cells;” retrieved online:DOI:10.1039.d1na00075f; The Ro… [cited by applicant]
Gao; “C60:LiF hole blocking layer for Bulk-Heterojunction solar cells;” Thesis presented to Graduate Department of Materials Science and Engineering; University of Toronto; 2010; pp. 1-68. [cited by applicant]