Carbon-Based Printable Perovskite Solar Cells with a Mesoporous TiO2 Electron Transporting Layer Derived from Metal–Organic Framework NH2-MIL-125

Applying metal–organic framework (MOF) materials to perovskite solar cells (PSCs) is an innovative and promising direction in the current photovoltaic field, especially in low-cost carbon-based PSCs without hole transport layer. Herein, a novel mesoporous anatase TiO 2 nanocrystalline with pie morphology, large specific surface area (SSA), and outstanding wettability is successfully prepared by sintering the NH 2 -MIL-125 at 500 °C for 6 h. The TiO 2 derived from NH 2 -MIL-125 possesses excellent penetration and crystallinity of perovskite in the electron transporting layer (ETL), and exhibits appropriate work function which matches relatively better with the conduction band of perovskite. Meanwhile, the power conversion efficiencies (PCEs) of the two PSC devices based on the as-prepared TiO 2 are 13.49% and 12.55%, respectively. Moreover, both of these devices exhibit good stability.