Design and Characterization of Nanostructured Ag₂O-Ag/Au Based on Al₂O₃ Template Membrane for Photoelectrochemical Water Splitting and Hydrogen Generation

Abstract

This study considers the progress of our previous study for hydrogen generation depends on the highly ordered metal oxide/plasmonic materials. This study reports the preparation of Ag2O-Ag/Au on the Al2O3 template (Ag2O-Ag/Au/Al2O3) for photocatalytic sewage water splitting and H2 gas production. Ni imprinting, followed by two-step anodization procedures, prepare the Al2O3 template. Ag2O-Ag and Au materials are prepared inside the template using electrochemical deposition and sputter coating methods, respectively. The chemical structure is confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses, in which all the peaks characterized by Ag2O, Ag, Au, and Al2O3 are confirmed. The scanning electron microscope (SEM) images confirm the preparation of a highly ordered hexagonal Al2O3 template with a pore wide of about 350 nm. Ag2O-Ag/Au accept the same morphology after the deposition process, in which the materials are deposited inside and on the Al2O3 template, in which the hexagonal pores are still opened after the deposition process. These open pores increase the surface area and then enhance the optical and electrical properties. For the H2 generated from sewage water, the produced Ag2O-Ag/Au on the Al2O3 photoelectrode achieved an incident to photon conversion efficiency (IPCE) of 30%. Additionally, the impact of light wavelength and intensity on photoelectrode performance is evaluated. Under increasing the light total power from 25 to 75 mW.cm−2, the current density (Jph) value goes up from 8.9 to 9.5 mA.cm−2. The current study’s findings show promising results for resolving the issue of energy in remote areas by turning wastewater into hydrogen fuel.

Keywords

• aluminum template
• nanoporous
• photoelectrode
• sewage water
• hydrogen generation
• water splitting