Vapor‐Phase Grain‐Boundary Anchoring Enables Molecular Toughening and Record Bending Endurance in Pilot‐Scale Roll‐to‐Roll‐Printed Flexible Perovskite Modules
Abstract
ABSTRACT Flexible lead‐halide perovskite solar modules with carbon electrodes (C‐fPSMs) are promising for printed photovoltaics due to their low cost and compatibility with roll‐to‐roll (R2R) fabrication. However, the mechanical fragility of microcrystalline perovskite films, arising from their high grain‐boundary density, limits their practical application. Here, we report a vapor‐phase grain‐boundary anchoring strategy via thiol vapor annealing to molecularly toughen printed perovskite layers. Thiol molecules interact with intermediate species and preferentially anchor at surfaces and grain boundaries, reprogramming crystallization across the film. This chemomechanical conditioning promotes grain growth, reduces trap density, and transforms the deformation behavior from brittle fracture to ductile strain accommodation, as evidenced by reduced Young's modulus, increased yield strain, and significantly enhanced fracture toughness. As a result, treated devices retain 93% of their initial performance after 25 000 bending cycles, representing a new benchmark for flexible perovskite cells. In addition, improved film uniformity and interfacial contact enable power conversion efficiencies of 15.7% for R2R‐printed cells and 12.1% for modules (20.25 cm 2 ), with scalability demonstrated up to 900 cm 2 (17.26%). This work provides a scalable strategy to simultaneously enhance mechanical robustness and photovoltaic performance.
Article Details
Authors (19)
Lirong Dong
Viktor Rehm
Institute of Materials for Electronics and Energy Technology (i‐MEET) Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Shudi Qiu
Zexian Han
Institute of Materials for Electronics and Energy Technology (i‐MEET) Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Naveen Harindu Hemasiri
Helmholtz Institute Erlangen‐Nürnberg For Renewable Energy (HI ERN), Institute for Photvoltaics (IMD‐3) Forschungszentrum Jülich GmbH Immerwahrstrasse 2 Erlangen Germany
Michael Wurmshuber
Institute of General Materials Properties Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Michael Wagner
Cindy‐Ly Tavera‐Méndez
Erlangen Center for Interface Research and Catalysis Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Dorothea Wisser
Erlangen Center for Interface Research and Catalysis Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Chaohui Li
Faculty of Engineering, Department of Material Science
Robin Basu
Institute of Materials for Electronics and Energy Technology (i‐MEET) Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Leopold Lahn
Faculty of Engineering, Department of Material Science
Olga Kasian
Faculty of Engineering, Department of Material Science
Sarmad Feroze
Institute of Materials for Electronics and Energy Technology (i‐MEET) Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Wolfgang Heiss
Institute of Materials for Electronics and Energy Technology (i‐MEET) Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Andreas Distler
Institute of Materials for Electronics and Energy Technology (i‐MEET) Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Hans‐Joachim Egelhaaf
Institute of Materials for Electronics and Energy Technology (i‐MEET) Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
Fu Yang
Department of Pharmacology and Cancer Biology, Duke University School of Medicine
Christoph J. Brabec
Institute of Energy Materials and Devices - Photovoltaics (IMD-3)