Magnetron sputtered Al-doped NiOx films as a hole transport layer for perovskite solar cells

NiO x is an ideal replacement material for organic hole transport layers, due to its chemical stability and low cost. However, the inherent insulating properties of NiO x films and the post-processing process of solution preparation have been limiting their application and development. Herein, high-quality Al y Ni 1-y O x hole transport layers were prepared by magnetron sputtering at room temperature without further processing. Simulation and experimental results showed that Al atoms enhance the concentration of holes in NiO x films, thus improving the electrical conductivity. In addition, the Al y Ni 1-y O x films exhibited match band alignment with perovskite films, enabling the improved charge transfer and exaction. Furthermore, the perovskite film quality was improved by the Al y Ni 1-y O x passivation. These factors resulted in an improvement in the power conversion efficiency of 5.4%, compared with undoped NiO x -based perovskite solar cells. This work provides a prospective reference for the high-throughput production of perovskite solar cells.