Stopping Phase Separation Enables Durable Wide‐Bandgap Photovoltaic Perovskites

X Xiao‐Ying He (State Key Laboratory of Bioinspired Interfacial Materials Science Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou China) B Bin Song K Kai‐Li Wang (Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China) N Nan Li L Lei Huang (BLSA-ZJU Research Center and Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.) R Rui‐Hao Qin (State Key Laboratory of Bioinspired Interfacial Materials Science Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou China) J Jing Chen C Chun‐Hao Chen (Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China) Y Yu Xia I Ilhan Yavuz Y Yan‐Hui Lou (College of Energy Soochow Institute for Energy and Materials Innovations Soochow University Suzhou China) Z Zhao‐Kui Wang (Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China)

Abstract

Abstract Light‐induced halide segregation presents a fundamental barrier to the longevity of wide‐bandgap (WBG) mixed‐halide perovskites. Herein, a multifunctional ionic polymer, polyquaternium‐37, is reported as an effective grain boundary passivator to inhibit the degradation pathway. This dual‐interaction mechanism concertedly arrests halide migration at grain boundaries, thereby suppressing local electric‐field and ultimately curbing light‐induced phase separation. Consequently, the modified WBG perovskites demonstrate robust photostability under light stress. The champion inverted perovskite photovoltaic device delivers a power conversion efficiency (PCE) of 22.86% under AM 1.5G illumination and an outstanding indoor PCE of 43.19% under 1000 lux. Remarkably, the modified device exhibits a projected T 90 lifetime exceeding 10 000 h under continuous indoor light cycling. This work pioneers a facile solution to halide segregation via grain boundary engineering, paving the way for operationally stable WBG perovskite photovoltaics.

Article Details

Volume / Issue Vol. 38, Issue 7
Published February 01, 2026
ISSN 0935-9648
Publisher Unknown Publisher

Journal Info

Advanced Materials

Unknown Publisher

ISSN: 0935-9648 Physical Sciences

Authors (12)

X

Xiao‐Ying He

State Key Laboratory of Bioinspired Interfacial Materials Science Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou China

B

Bin Song

K

Kai‐Li Wang

Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China

N

Nan Li

L

Lei Huang

BLSA-ZJU Research Center and Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.

R

Rui‐Hao Qin

State Key Laboratory of Bioinspired Interfacial Materials Science Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou China

J

Jing Chen

C

Chun‐Hao Chen

Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China

Y

Yu Xia

I

Ilhan Yavuz

Y

Yan‐Hui Lou

College of Energy Soochow Institute for Energy and Materials Innovations Soochow University Suzhou China

Z

Zhao‐Kui Wang

Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China