Polymer-engineered perovskite solar cells: synergistic strategies for multiscale stability and high-efficiency photovoltaics

Perovskite solar cells (PSCs) have immense promise as next-generation photovoltaic technology, driven by their high efficiency, solution processability, and low fabrication costs. However, challenges such as imperfect film quality, environmental instability, and mechanical fragility continue to impede their commercialization. Polymers, with their tunable functional groups, robust thermal stability, and adaptive cross-linking architectures, emerge as versatile tools to address these limitations. This review highlights the multifaceted roles of polymers in PSCs, where tailored molecular interactions regulate crystallization dynamics, suppress ion migration, optimize charge transport, and enhance mechanical flexibility. Hydrophobic polymer networks further shield devices from moisture and oxygen ingress, while cross-linked frameworks mitigate lead leakage, aligning performance with environmental sustainability. By integrating defect passivation, interfacial engineering, and dynamic self-healing mechanisms, polymers enable a synergistic approach to balancing efficiency and durability. Future perspectives focus on advancing multifunctional polymer designs, scalable processing techniques, and bio-inspired stabilization strategies to propel perovskite optoelectronics toward practical applications.