“…NiO is known to be a nontoxic material, especially compared to other transition semiconductors [ 3 ]. Due to these unique properties, NiO x thin films become multipurpose materials in various applications such as electrochromic (EC) applications [ 4 ]. NiO manifests high optical contrast, fast switching times, good cycling, and anodic coloration, which is very promising for a counter electrode layer in complementary EC devices [ 5 , 6 , 7 ], supercapacitors [ 8 ], as a hole transport layer of perovskite solar cells [ 9 ], highly sensitive gas sensors [ 2 ], transparent conducting oxides, spin-valve giant magnetoresistive sensors, chemical sensor applications, Schottky diodes, and metal oxide field-effect transistors (MOSFETs) [ 10 ].…”