High Efficiency and Stability of Inverted Perovskite Solar Cells Using Phenethyl Ammonium Iodide-Modified Interface of NiO and Perovskite Layers.

Hole transport layer NiO-based inverted perovskite solar cells (PSCs) have advantages of simple fabrication, low temperature, and low cost. Furthermore, the p-type NiO material compared to that of typical n-type SnO for PSCs has better photostability potential due to its lower photocatalytic ability. However, the NiO layer modified by some typical materials show relatively simple functions, which limit the synthesized performance of NiO-based inverted PSCs. Phenethyl ammonium iodide (PEAI) was introduced to modify the NiO/perovskite interface, which can synchronously contribute to better crystallinity and stability of the perovskite layer, passivating interface defects, formed quasi-two-dimensional PEAPbI perovskite layers, and superior interface contact properties. The PCEs of PSCs with the PEAI-modified NiO/perovskite interface was obviously increased from 20.31 from 16.54% compared to that of the reference PSCs. The PSCs with PEAI modification remained 75 and 72% of the original PCE values aging for 10 h at 85 °C and 65 days in a relative humidity of 15%, which are superior to the original PCE values (47 and 51%, respectively) for the reference PSCs. Therefore, PSCs with the PEAI-modified NiO/perovskite interface show higher PCEs and better thermal stability and moisture resistance.