Ce³⁺ doping enhanced electrical and UV photo-sensing properties of NiO nanostructures

In this study, photodetectors were constructed utilising Ce³⁺ ions doped NiO nanoparticles in order to enhance the detection capabilities for ultraviolet (UV) radiation. The NiO nanostructures, which were doped with varying concentrations of Ce³⁺ at levels of pure, 1%, 2%, and 3%, exhibited crystal sizes measuring 6 nm, 12 nm, 15 nm, and 19 nm, respectively. The morphological characteristics of Ni_1-xCe_xO nanoparticles, encompassing various levels of dopant concentrations (X = 0%, 1%, 2%, and 3%), were confirmed through the utilisation of transmission electron microscopy images. The morphology of NiO material is influenced by the introduction and concentration of dopants. Based on the results obtained from UV–visible absorption spectroscopic measurements, it can be inferred that the incorporation of Ce³⁺ ions into the system led to an enhancement in the absorption properties. The observed bandgap values corresponding to different levels of Ce³⁺ doping, specifically 0%, 1%, 2%, and 3%, are 3.51 eV, 3.43 eV, 3.39 eV, and 3.2 eV, respectively. The observed photoluminescence spectrum indicates that Ce³⁺ ions possess the ability to effectively trap and retain excited electrons within an energy level that lies between the ground and excited states. This phenomenon significantly prolongs the lifetime of excitons. The utilisation of Ce³⁺-doped NiO sensors in UV photodetection resulted in a notable enhancement in both conductivity and photocurrent. The photodetector, fabricated utilising a 3% concentration of Ce³⁺ doped NiO, has demonstrated a responsivity of 20 × 10^–2 AW⁻¹, a detectivity of 11.31 × 10⁹ Jones, and an external quantum efficiency (EQE) of 56%.