Asymmetric Lamellar Templating of the Perovskite/C <sub>60</sub> Interface for Scalable Inverted Perovskite Photovoltaics

T Taeyoon Ki (Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea) J Jong‐Guk Ahn (Center For Quantum Conversion Research (QCR) Institute For Basic Science (IBS) Gwangju Republic of Korea) S Sangcho Kim (Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea) S Sangjin Kim (Department of Physics, University of Illinois Urbana-Champaign 1 , Urbana, Illinois 61801,) M Min‐Ho Lee (School of Electrical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon Republic of Korea) I In‐Wook Hwang (Advanced Photonics Research Institute (APRI) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea) J Jinju Jeong (Department of Energy Engineering Korea Institute of Energy Technology (KENTECH) Naju Jeollanam‐do Republic of Korea) S Soobin Shim (Department of Materials Engineering and Convergence Technology Gyeongsang National University Jinju Gyeongnam Republic of Korea) J Jaeboong Ahn (Department of Chemistry College of Natural Sciences Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea) J Jun Hong Park S Seungjin Lee J Jung‐Yong Lee (School of Electrical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon Republic of Korea) Y Yousoo Kim (Surface and Interface Science Laboratory, RIKEN 1 , 2-1 Hirosawa, Wako, Saitama 351-0198,) J Ju‐Hyeon Kim (Department of Physics, Chemistry and Biology (IFM) Linköping University Linköping Sweden) H Hongkyu Kang (Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea) S Sukwon Hong (Department of Chemistry College of Natural Sciences Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea) K Kwanghee Lee (Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea)

Abstract

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 &gt; 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.

Article Details

Volume / Issue Vol. 1, Issue 1
Published July 30, 2026
ISSN 0935-9648
Publisher Unknown Publisher

Journal Info

Advanced Materials

Unknown Publisher

ISSN: 0935-9648 Physical Sciences

Authors (17)

T

Taeyoon Ki

Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea

J

Jong‐Guk Ahn

Center For Quantum Conversion Research (QCR) Institute For Basic Science (IBS) Gwangju Republic of Korea

S

Sangcho Kim

Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea

S

Sangjin Kim

Department of Physics, University of Illinois Urbana-Champaign 1 , Urbana, Illinois 61801,

M

Min‐Ho Lee

School of Electrical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon Republic of Korea

I

In‐Wook Hwang

Advanced Photonics Research Institute (APRI) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea

J

Jinju Jeong

Department of Energy Engineering Korea Institute of Energy Technology (KENTECH) Naju Jeollanam‐do Republic of Korea

S

Soobin Shim

Department of Materials Engineering and Convergence Technology Gyeongsang National University Jinju Gyeongnam Republic of Korea

J

Jaeboong Ahn

Department of Chemistry College of Natural Sciences Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea

J

Jun Hong Park

S

Seungjin Lee

J

Jung‐Yong Lee

School of Electrical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon Republic of Korea

Y

Yousoo Kim

Surface and Interface Science Laboratory, RIKEN 1 , 2-1 Hirosawa, Wako, Saitama 351-0198,

J

Ju‐Hyeon Kim

Department of Physics, Chemistry and Biology (IFM) Linköping University Linköping Sweden

H

Hongkyu Kang

Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea

S

Sukwon Hong

Department of Chemistry College of Natural Sciences Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea

K

Kwanghee Lee

Heeger Center for Advanced Materials (HCAM) Gwangju Institute of Science and Technology (GIST) Gwangju Republic of Korea