Synergistic enhancement of carbon-based perovskite solar cells via Ce-MOF-derived interfacial layer and hot pressing

This study presents a facile synthesis of cerium-based metal–organic frameworks (Ce-BTC) and their subsequent pyrolysis into nanorod-shaped CeO 2 -BTC for interfacial engineering in carbon-based perovskite solar cells (C-PSCs). The optimized FTO/SnO 2 /CH 3 NH 3 PbI 3 /CeO 2 -BTC/Carbon architecture achieves a maximum power conversion efficiency (PCE) of 14.63%, representing a 31.09% enhancement over the baseline device. This improvement stems from multiple synergistic effects: CeO 2 -BTC demonstrates exceptional charge extraction capability, establishes superior interfacial contact, and directly coordinates with perovskite through Pb-O bond formation. Furthermore, the C=O groups effectively anchor uncoordinated Pb 2 + ions, modulating perovskite crystallization kinetics and improving film quality. Subsequent hot-pressing treatment elevates the champion device PCE to 15.12% through enhanced interfacial compactness. Remarkably, the optimized devices retain 93.26% of initial efficiency after 700 h of ambient air exposure without encapsulation, demonstrating exceptional environmental stability. This work provides a comprehensive strategy for developing high-performance, durable carbon-based perovskite photovoltaics through rational interface engineering.