Investigations on the synthesis and characterization of silver-doped MoO₃ thin films for photocatalytic applications

In this study, we aimed to enhance the photocatalytic performance of molybdenum oxide (MoO₃) thin films by doping with silver (Ag) via a spray pyrolysis technique. The primary objective for silver incorporation was intended to introduce additional energy levels into the band structure of MoO₃, improving its efficiency. Structural, optical, and photocatalytic properties were analyzed using X-ray diffraction (XRD) and optical spectroscopy. XRD results confirmed an orthorhombic phase with a (040) preferential orientation for all samples. Optimal crystallinity was observed with 2% Ag doping, yielding an 84 nm crystallite size, while higher doping levels reduced crystallite size. Band gap energy narrowed from 3.07 eV (undoped) to 2.94 eV (2% Ag-doped), indicating electronic structure changes. Impedance spectroscopy revealed superior electrical properties at 4% Ag doping, enhancing charge transport. Photocatalytic performance, assessed via dye degradation, showed significant improvement with silver doping, the degradation rate peaking at 4% Ag. These results demonstrate that silver doping optimizes structural and electronic properties of MoO₃ thin films, leading to enhanced photocatalytic activity.