Fabrication of nanostructured NiO and NiO:Cu thin films for high-performance ultraviolet photodetector

Abstract In this work, pure NiO and NiO:Cu based photodetectors with different concentrations of Cu dopants (0, 0.5,1.0, and 1.5 wt%) were coated on glass substrates by using a simple, low cost nebulizer spray pyrolysis technique. Their structural, morphological, optical (UV–Vis absorption and photoluminescence), and ultraviolet (UV) sensing features were characterized with state-of-the-art analytical techniques. The structural studies confirm that the prepared films have crystalline nature and possess a cubic structure. From the absorption measurement, the optical bandgap (Eg) of the deposited films decreases with the increase in Cu dopants. Photoluminescence study illustrates that 1.0% of Cu doping significantly improves the physical property of the NiO:Cu films and also its UV sensing study suggests that the 1.0% of NiO:Cu film could be better suited for high-speed optoelectronic devices due to their high Responsivity (0.202 AW-1), External quantum efficiency (47%), and Detectivity (5.9 × 109 jones) values. A possible mechanism of the photodetector performance under air and UV illumination is also discussed in this work.