Development of Visible-Blind UV Photodetector Using Solution Processed Ag-ZnO Nanostructures

In this work, we have reported completely solution-processed Ag-ZnO nanostructures towards the development of highly selective, visible-blind and stable UV photodetector. The Ag nanoparticles were deposited over ZnO nanostructures via photochemical reduction process. Comparing to pristine ZnO, the Ag decorated ZnO has demonstrated significant suppression in the leakage current from 9.83×10 ^-11 A to 7.16×10 ^-12 A at an applied bias of 10 V. The photosensitivity has been improved from 7.6×10 ⁵ to 2.2×10 ⁶ at 330 nm wavelength. Moreover, the UV to visible rejection ratio (R _(330nm) /R _(650nm) ) is enhanced from 67 to 1.1×10 ⁴ . The fabricated Ag-ZnO nanostructured device showed stable response under UV illumination with improved rise time and fall time of 30 s and 65 s, respectively. The work has immense potential to replace the existing complex and costly device synthesis processes with simple and cost-effective solution-based approach to develop highly reliable and visible blind UV photodetectors.