Spontaneous Heterointerface Modulation by a Methylammonium Tetrafluoroborate Additive for a Narrow-Bandgap FAPbI3 Photoabsorber in Perovskite Solar Cells

Over the past decade, the photovoltaic (PV) performance of perovskite solar cells (PSCs) has been considerably improved with the development of perovskite photoabsorbers. Among these, formamidinium-lead-iodide (FAPbI