Breaking Barriers in FAPbI ₃ Perovskite Photovoltaics: Synergistic Strategies for Phase Stability, Defect Mitigation, and Scalable Production

Abstract

Formamidinium lead triiodide (FAPbI 3 ) perovskite solar cells remain central to next‐generation photovoltaic research because of their near‐optimal bandgap and high power conversion efficiencies, yet their long‐term operational stability continues to limit technological maturity. This review provides a comprehensive evaluation of recent advances aimed at stabilizing the photoactive α‐FAPbI 3 phase and mitigating the structural and defect processes that underpin degradation. We integrate these developments with original first‐principles density functional theory calculations that probe intrinsic phase energetics and reveal how targeted B‐site doping influences structural robustness. Strategies highlighted include lattice‐strain modulation, multifunctional defect‐passivation chemistries, machine‐learning‐assisted compositional design, and scalable vapor‐ and ink‐based fabrication techniques that bridge laboratory processing with industrial relevance. Together, these approaches outline the materials design principles and engineering innovations needed to advance FAPbI 3 towards durable, high‐efficiency perovskite photovoltaic technologies.