Photoelectrochemical, Structural, and Optical Investigations of Silver-Doped Cupric Oxide Films Fabricated via Electrodeposition

Bensenouci, Halima and Belgroune, Ahlam and Cheriet, Abderrahmane and Aissani, Linda and Hamdi, Ahmed and Ferhat, Mahmoud and Boulerba, Djilali and Keziz, Ahcene and Ismael, Ali and Taha, Taha Abdel Mohaymen (2025) Photoelectrochemical, Structural, and Optical Investigations of Silver-Doped Cupric Oxide Films Fabricated via Electrodeposition. ECS Journal of Solid State Science and Technology, 14 (9): 093002. ISSN 2162-8769

Abstract

In this work, we report for the first-time the impact of silver doping on the structural, electrical, and optical properties of CuO thin films synthesized through a low-energy electrodeposition method. Both pure and Ag-doped CuO films were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy, UV–visible spectroscopy, and electrochemical impedance spectroscopy (EIS). The photocurrent response was examined in a photo-electrochemical cell. FE-SEM revealed a significant morphology shift from rod-like grains to compact globular structures upon Ag doping. XRD confirmed a monoclinic phase, with preferred orientations along (002) and (111) planes. The intensity ratio I(111)/I(002) decreased from 1.169 for pure CuO to 1.060 with 2% Ag doping, then increased to 1.289 for 5% Ag, indicating changes in growth orientation. The crystallite size decreased from 29.8 nm (pure) to 27.8 nm with 2%Ag doping. A band gap narrowing was observed of from 2.25 eV (undoped) to 1.62 eV at 5%Ag. EIS shows a decrease in charge transfer resistance Rct from 49.86 Ω to 30.77 Ω, confirming enhanced conductivity and photo-response. These results demonstrate that Ag doping via low-energy electrodeposition effectively tunes the properties of CuO thin films, offering a novel and promising route for optoelectronic applications.