Overcoming the Limitations of Sputtered Nickel Oxide for High‐Efficiency and Large‐Area Perovskite Solar Cells

Abstract Perovskite solar cells (PSCs) are one of the promising photovoltaic technologies for solar electricity generation. NiO x is an inorganic p‐type semiconductor widely used to address the stability issue of PSCs. Although high efficiency is obtained for the devices employing NiO x as the hole transport layer, the fabrication methods have yet to be demonstrated for industrially relevant manufacturing of large‐area and high‐performance devices. Here, it is shown that these requirements can be satisfied by using the magnetron sputtering, which is well established in the industry. The limitations of low fill factor and short‐circuit current commonly observed in sputtered NiO x ‐derived PSCs can be overcome through magnesium doping and low oxygen partial pressure deposition. The fabricated PSCs show a high power conversion efficiency of up to 18.5%, along with negligible hysteresis, improved ambient stability, and high reproducibility. In addition, good uniformity is also demonstrated over an area of 100 cm 2 . The simple and well‐established approach constitutes a reliable and scale method paving the way for the commercialization of PSCs.