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Vol. 18 (2026)

Homogenize Strain Distribution via Molecular Network Engineering for Mechanically Reliable Flexible Perovskite Solar Cells

https://doi.org/10.1007/s40820-026-02079-x
Fuhao Han
Key Lab for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High‑Efficiency Display and Lighting Technology, School of Nanoscience and Materials Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, People’s Republic of China
Zuhong Zhang
Key Lab for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High‑Efficiency Display and Lighting Technology, School of Nanoscience and Materials Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, People’s Republic of China
Hongzhuo Wu
Key Lab for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High‑Efficiency Display and Lighting Technology, School of Nanoscience and Materials Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, People’s Republic of China
Hongxing Yuan
Henan Key Laboratory of Advanced Conductor Materials, Institute of Materials, Henan Academy of Sciences, Zhengzhou 450001, People’s Republic of China
Linfeng Lu
Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, 239 Zhangheng Road, Shanghai 201204, People’s Republic of China
Zhenhuang Su
Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, 239 Zhangheng Road, Shanghai 201204, People’s Republic of China
Xingyu Gao
Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, 239 Zhangheng Road, Shanghai 201204, People’s Republic of China
Qi Cao
Huairou Lab, Minist Renewable Energy, Beijing 101400, People’s Republic of China
Zhihao Li
Key Lab for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High‑Efficiency Display and Lighting Technology, School of Nanoscience and Materials Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, People’s Republic of China

Corresponding Author: Zhihao Li

lizhihao@henu.edu.cn

Nano-Micro Letters, Vol. 18 (2026), Article Number: 218

Abstract

Flexible perovskite solar cells (FPSCs) suffer from strain localization-induced mechanical degradation, primarily due to heterogeneous strain distribution at grain boundaries. Herein, we propose a molecular engineering approach involving a crosslinked Methacrylic anhydride (MA) to construct a 3D crosslinking network within perovskite films. This molecular-scale network effectively redistributes localized strain into a more homogeneous pattern, as indicated by reduced strain variance and a lower Young’s modulus. Simultaneously, the MA network modulates crystallization kinetics, leading to enlarged grain sizes, enhanced (001) orientation, and decreased defect density. Together, these effects minimize strain concentration and promote elastic strain release, thereby suppressing microcrack formation at grain boundaries. As a result, the optimized rigid perovskite solar cells exhibit superior conversion efficiency of 26.42%, while the FPSCs reach 25.03% with excellent mechanical stability.


Highlights:
1 Dual-function molecular ligand (MA) can coordinate with Pb2+ to passivate defect at grain boundaries and undergoes in-situ polymerization to form a stress-buffering network.
2 Attributing to the simultaneous defect suppression and strain homogenization, the MA-modified perovskite solar cells demonstrate high photovoltaic performance with power conversion efficiency up to 26.42% (rigid) and 25.03% (flexible).
3 The MA-modified devices demonstrate excellent stability under various environmental stress conditions, including thermal aging, light irradiation, and bending.

Keywords

Flexible perovskite solar cells Homogenize strain distribution Crosslinking Mechanical toughness Crystallization
Han, Fuhao, Zuhong Zhang, Hongzhuo Wu, Hongxing Yuan, Linfeng Lu, Zhenhuang Su, Xingyu Gao, Qi Cao, and Zhihao Li. 2026. “Homogenize Strain Distribution via Molecular Network Engineering for Mechanically Reliable Flexible Perovskite Solar Cells”. Nano-Micro Letters 18 (January):218. https://doi.org/10.1007/s40820-026-02079-x.
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