Room-temperature processed plasma activated nickel oxide film for wide-bandgap perovskite solar cells

The nickel oxide (NiOx) film is often employed as a hole transport layer for the production of high-performance inverted perovskite solar cells due to its exceptional chemical stability, high hole mobility, and matching energy level structure. Among various techniques for preparing NiOx, E-beam evaporation-based NiOx films show great promise owing to their low fabrication temperature and excellent photoelectric properties. Herein, an ion bombardment source was used to generate oxygen plasma through the bombardment of oxygen molecules, which subsequently oxidized the non-stoichiometric NiOx. Experimental findings demonstrate that this method substantially enhances the electrical and optical properties of the NiOx film. We utilized a room-temperature-processed NiOx film as a hole transport layer to fabricate inverted wide-bandgap perovskite solar cells, resulting in a champion device efficiency of 17.82%. It is anticipated that the NiOx films produced via this approach will be widely adopted in the industrialization of perovskite solar cells.