Flexible lead-free perovskite solar cell with Artificial Intelligence integration: Application, challenges, and future perspectives

Perovskite solar cells (PSCs) have become a ‘rising star’ in the last few decades because of their high-power conversion efficiency (PCE), which has risen from 3.8% in 2009–29.1% in 2026, as verified by the National Renewable Energy Laboratory (NREL), along with incredibly inexpensive and simple fabrication methods. Despite the significant benefits and PCE that PSCs have attained, the toxicity problem with lead has delayed their commercial entry into the market. Additionally, conventional PSCs are typically fabricated on rigid glass substrates with brittle transparent electrodes, which limits their mechanical compliance and conformal integration on curved or wearable surfaces. In addition, glass-based modules are relatively heavy and bulky, increasing transportation, installation, and encapsulation costs, particularly for building-integrated or aerospace applications. These rigidity and weight constraints strongly motivate the development of lightweight, bendable lead-free flexible perovskite solar cells (LFFPSCs) using polymer substrates and low-temperature processing. This review provides a detailed account of the latest developments in LFFPSCs. There are thorough explanations and discussions on a number of important topics, such as charge transport layers, substrates, perovskite materials, electrode materials, and device design. In this review, an extensive discussion is provided on the various applications of LFFPSCs, the impact of AI integration, and key factors to improve efficiency and stability. Finally, the review discusses the challenges and makes predictions about the technologies, as well as the futuristic uses that can be applied to LFFPSCs.