Polymer-enabled self-healing and performance recovery: a route to significantly enhance durability and extend lifespan of perovskite-based photovoltaics

Perovskite solar cells (PSCs) combine exceptional power conversion efficiencies with low-cost solution-based processing but remain hindered by environmental instability, mechanical fragility on flexible substrates, and lead leakage. This review evaluates polymer-enabled self-healing strategies for both rigid and flexible PSCs. Rigid PSCs benefit from polymeric scaffolds that sequester volatile degradation products to enable in situ perovskite recrystallization, environmental stimulus-responsive additives that continuously neutralize emerging defects, and self-healing outer encapsulants that autonomously mend impact-induced damage while also reducing lead leakage. In flexible devices, dynamic supramolecular networks based on hydrogen bonding, ionic interactions, and reversible covalent linkages facilitate autonomous repair of bending-induced microcracks, leading to nearly complete restoration of initial performance after extensive deformation cycles. Multifunctional polymer design holds promise for enhancing intrinsic stability by passivating defects at grain boundaries, enhancing extrinsic resistance to moisture and thermal stress, and increasing mechanical robustness under cyclic bending. Future research directions include expanding self-healing capabilities across all PSC functional layers, optimizing healing kinetics, and addressing scalability for industrial manufacturing. Overall, polymer-enabled self-healing approaches are poised to play a critical role in the commercialization of highly robust perovskite-based photovoltaics with enhanced operational stability.