Synthesis of porous thin silver films and their application for hydrogen peroxide sensing

Highlights: • Thin Ag-Zn alloy films were obtained by DC electrodeposition. • Porous thin Ag films were fabricated be selective etching of Ag-Zn alloys. • The developed electrode has excellent catalytic activity toward reduction of H₂O₂. • The prepared sensor was applied for determination hydrogen peroxide in real samples. - Abstract: Porous thin silver films were fabricated by electrochemical deposition of Ag-Zn alloys followed by a selective dealloying of zinc component. The Ag-Zn alloys were synthesized at various operating conditions including: different Ag⁺/Zn²⁺ molar ratio in the electrolyte (1:1 and 1:3), current density (0.2–20 mA cm⁻²), and time of electrodeposition (5–60 min). The deposited thin alloy films were characterized with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The effect of dealloying time on morphology of resulting films was studied. The formation of alloys and their chemical composition were confirmed by XRD and EDS spectra. The developed porous thin Ag film electrode showed good electrocatalytic activity toward reduction of hydrogen peroxide. The influence of interfering compounds such as ascorbic acid, uric acid and glucose was studied. The proposed method with amperometric detection was applied with success, satisfying accuracy and precision to determination of hydrogen peroxide in real samples.