Positional Methylation Isomer Additives Regulate the Degradation Pathway of Perovskites

Z Zhenda Huang (Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China) B Boyuan Liu Z Zheng Liang (Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering) H Huifen Xu (Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China) H Houwei He (Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China) W Wanting Liu H Hongmin Zhou Y Yong Zhang J Jiajiu Ye (Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China) X Xu Pan (School of Integrated Circuits, Harbin Institute of Technology (Shenzhen) 1 , Shenzhen 518055,)

Abstract

ABSTRACT Multi‐active‐site additives with strong reactivity are an effective strategy to continuously improve device efficiency, and also contribute to the long‐term stability of perovskite solar cells (PSCs). However, achieving efficient interaction between all active sites and the perovskite remains a critical challenge. Among various structural modifications, methyl substitution, the simplest functional unit in organic chemistry, offers a unique methylation effect that strongly depends on its positional configuration within a molecule, thereby providing a promising approach to modulate additive reactivity. In this study, we designed and investigated two positional methylation isomers, 1‐methylhydantoin (1‐MH) and 5‐methylhydantoin (5‐MH), and demonstrate rational positional methylation can significantly enhance the multisite reactivity of additives with perovskite materials. While both isomers contribute to improved device efficiency, they exhibit markedly different effects on device stability. Notably, the incorporation of 5‐MH enabled a power conversion efficiency (PCE) of 26.84% (certified at 26.78%), and delivered outstanding operational stability, retaining 92% of its initial PCE after 2000 h under the ISOS‐L2 protocol.

Article Details

Volume / Issue Vol. 38, Issue 20
Published April 01, 2026
ISSN 0935-9648
Publisher Unknown Publisher

Journal Info

Advanced Materials

Unknown Publisher

ISSN: 0935-9648 Physical Sciences

Authors (10)

Z

Zhenda Huang

Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China

B

Boyuan Liu

Z

Zheng Liang

Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering

H

Huifen Xu

Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China

H

Houwei He

Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China

W

Wanting Liu

H

Hongmin Zhou

Y

Yong Zhang

J

Jiajiu Ye

Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid‐State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei China

X

Xu Pan

School of Integrated Circuits, Harbin Institute of Technology (Shenzhen) 1 , Shenzhen 518055,