Enhancing carrier transport in Cs2AgBiBr6 double perovskites through multifunctional ferroelectric polymer doping

T Tongming Rao (Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,) W Wanjiang Wang (Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,) J Jie Chen D Daquan Chen (Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,) C Chaoling Zhou (Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,) P Ping Lin (State Key Laboratory of Structural Chemistry, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China) Z Zhenyi Ni C Can Cui L Lingbo Xu (Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,)

Abstract

Cs2AgBiBr6 lead-free double perovskites are promising materials for optoelectronic applications but suffer from limited carrier transport due to defects and strong electron–phonon coupling. In this work, we introduce a multifunctional doping strategy using the ferroelectric polymer polyvinylidene fluoride (PVDF) to simultaneously address these challenges. PVDF modulates film crystallization to reduce defects, relaxes lattice strain to weaken electron–phonon coupling, and—after electrical polarization—provides a built-in electric field that promotes charge separation. As a result, PVDF-doped Cs2AgBiBr6 solar cells achieve a champion power conversion efficiency of 1.91%, representing a 40% improvement over the control device (1.36%), with much improved stability. This work presents a simple and effective approach to improving carrier dynamics in double perovskites for broader optoelectronic applications.

Article Details

Volume / Issue Vol. 128, Issue 24
Published June 15, 2026
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (9)

T

Tongming Rao

Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,

W

Wanjiang Wang

Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,

J

Jie Chen

D

Daquan Chen

Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,

C

Chaoling Zhou

Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,

P

Ping Lin

State Key Laboratory of Structural Chemistry, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

Z

Zhenyi Ni

C

Can Cui

L

Lingbo Xu

Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, School of Science, Department of Physics, Zhejiang Sci-Tech University 1 , Hangzhou 310018,