Ti₂CT_<i>x</i>‑MXeneas An Efficient Passivation Layer to Regulate the Vertical Growthof Perovskite Layers and Enhance the Performance of Solar Cells

The commercialization of perovskite solar cells (PSCs) is significantly impeded by their limited moisture stability. Integrating an effective passivation layer can serve as a protective barrier, enhancing stability under humid conditions and improving the device’s photoelectric performance. In this study, we utilized Ti₂CT_<i>x</i>-MXene, which was spin-coated onto the perovskite surface, which facilitated controlled vertical crystal growth and simultaneous band gap alignment. Our findings demonstrate that the inclusion of MXene effectively balances charge mobility, resulting in a promising power conversion efficiency (PCE) of 22.22% while maintaining robust stability. This study introduces a top-down approach for controlling perovskite morphology and directional growth, thereby enhancing the photovoltaic performance of the fabricated devices.