Towards sustainable and flexible solar energy: A review of perovskite solar cell technologies

Perovskite solar cells (PSCs) have experienced extraordinary development over the past decade, with power conversion efficiencies (PCEs) rapidly improving from 3.8% to approximately 26%. Among them, flexible solar cells (FPSCs) offer several unique advantages such as lightweight nature, mechanical flexibility, and compatibility with curved or portable surfaces. These features make FPSCs promising candidates to replace conventional rigid solar modules, particularly in building integrated photovoltaics, wearable electronics, and mobile power systems. This article systematically reviews the materials related advancement for FPSCs, particularly the innovations in substrates, charge transport layers, absorber layer, and the electrodes. The strategies for enhancing stability of the FPSCs by employing carbon-based electrodes have also been emphasized. Additionally, the recent progress in low-temperature and scalable fabrication techniques is discussed, alongside the major challenges encountered during FPSC synthesis. Degradation mechanisms that limit the long-term performance of FPSCs are examined, and an overview of their commercialization status is provided. This article serves as a valuable resource for researchers and stakeholders interested in current trends and future directions in flexible perovskite photovoltaics.