Magnetron sputtering NiO _x for perovskite solar cells

Perovskite solar cells (PSCs) have become a hot topic in the field of renewable energy due to their excellent power conversion efficiency and potential for low-cost manufacturing. The hole transport layer (HTL), as a key component of PSCs, plays a crucial role in the cell's overall performance. Magnetron sputtering NiO_x has attracted widespread attention due to its high carrier mobility, excellent stability, and suitability for large-scale production. Herein, an insightful summary of the recent progress of magnetron sputtering NiO_x as the HTL of PSCs is presented to promote its further development. This review summarized the basic properties of magnetron sputtering NiO_x thin film, the key parameters affecting the optoelectronic properties of NiO_x thin films during the magnetron-sputtering process, and the performance of the corresponding PSCs. Special attention was paid to the interfacial issues between NiO_x and perovskites, and the modification strategies were systematically summarized. Finally, the challenges of sputtering NiO_x technology and the possible development opportunities were concluded and discussed.