Plasmon induced green synthesized nano silver doped titania nanotubes array for photoelectrochemical (PEC) application

Abstract

The capillary effect of titanium nanotube arrays (TNTs) was used for in-situ deposition of green synthesized silver nanoparticles (AgNPs) to create hybrid Ag-TNT nanostructures. Titania is a well-known and well-established photocatalyst, although its applications are limited to the ultraviolet region. Under visible light irradiation, the silver nanoparticles, which are recognized for their plasmonics, create the ideal pair as an efficient photosensitizer to promote photocatalytic water splitting. In this approach, a green synthesis method was used to synthesize nano silver colloid, and the silver nanoparticles were then introduced to an anodized titanium plate for incorporation. The photocatalysts are characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), UV-VIS-diffuse reflectance spectra, Fluorescence spectroscopy, and X-ray photoelectron spectroscopy (XPS) to explore their structural and optical properties. Time-resolved photoluminescence (TRPL) spectroscopy was employed to understand the charger carrier kinetics and the electrons/holes recombination strategy using the bi-exponential decay function. The visible-light-driven hydrogen production activities of Ag-TNT photocatalysts were evaluated and the hydrogen production rate of Ag-TNT was 12 times higher than TNT. The surface plasmon resonance (SPR) effect of Ag-NPs improves visible-light harvesting and electron transport to the conduction band. The use of the capillary effect to deposit green AgNPs is a simple and promising method for improving Titania-based photocatalyst performance.