Asymmetric Lamellar Templating of the Perovskite/C <sub>60</sub> Interface for Scalable Inverted Perovskite Photovoltaics
ABSTRACT Scalable inverted perovskite solar cells require top interfaces that combine defect passivation with spatially uniform electron extraction as the device area increases. Low‐dimensional capping layers based on bulky spacer cations can suppress surface recombination, but poorly controlled molecular packing often introduces transport barriers and local interfacial heterogeneity. Here, we introduce indol‐3‐ylethylammonium iodide (Ind) as a π‐electron‐rich spacer cation for asymmetric lamellar templating at the perovskite/C 60 junction. The heteroatom‐polarized indole framework creates lateral electrostatic anisotropy within the aromatic plane, promoting face‐to‐face spacer association and aligning the lamellar interphase. The resulting π‐rich lamellar interphase suppresses interfacial recombination, preserves electron extraction, and improves spatial optoelectronic uniformity in large‐area devices. Ind‐based devices achieve a certified efficiency of 26.94% in small‐area cells and a certified module efficiency of 23.21% for a 25 cm 2 monolithic module. They further retain > 93% efficiency after 1000 h at 85°C and maintain 85% of their initial efficiency after 1800 h under continuous 1‐sun MPP tracking. These results identify lateral electrostatic anisotropy as a molecular design principle for scalable perovskite/C 60 top interfaces.
Authors
- Jong‐Guk Ahn (ORCID: https://orcid.org/0000-0001-5772-5668)
- Sukwon Hong (ORCID: https://orcid.org/0000-0002-2078-9630)
- Hongkyu Kang (ORCID: https://orcid.org/0000-0003-2890-9710)
- Sangcho Kim
- Taeyoon Ki (ORCID: https://orcid.org/0000-0002-8092-091X)
- Kwanghee Lee (ORCID: https://orcid.org/0000-0002-5907-8625)
- Jung‐Yong Lee (ORCID: https://orcid.org/0000-0002-5347-8230)
- Ju‐Hyeon Kim (ORCID: https://orcid.org/0000-0002-9216-615X)
- Yousoo Kim (ORCID: https://orcid.org/0000-0001-7730-0704)
- Jun Hong Park (ORCID: https://orcid.org/0000-0001-5138-1622)
- Min‐Ho Lee (ORCID: https://orcid.org/0009-0002-7992-9543)
- Seungjin Lee (ORCID: https://orcid.org/0000-0002-6318-0702)
- Sangjin Kim (ORCID: https://orcid.org/0000-0001-6665-9973)
- Soobin Shim (ORCID: https://orcid.org/0009-0006-6572-8416)
- In‐Wook Hwang (ORCID: https://orcid.org/0000-0002-9314-2598)
- Jinju Jeong
- Jaeboong Ahn
Institutions
- Linköping University (SE)
- Gyeongnam National University of Science and Technology (KR)
- Bunkyo University (JP)
- Korea Advanced Institute of Science and Technology (KR)
- Gyeongsang National University (KR)
- Interface (United States) (US)
- Gwangju Institute of Science and Technology (KR)
- Institute for Basic Science (KR)
- Korea Institute of Energy Research (KR)
- The University of Tokyo (JP)
Publication Details
- Journal
- Advanced Materials
- Published
- 2026-07-30
- DOI
- https://doi.org/10.1002/adma.74316
- Primary Topic
- Perovskite Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Research Foundation of Korea
- Korea Institute of Energy Technology Evaluation and Planning