Uniform formation and characterization of Au/TiO2 nanoparticles for electrokinetically assisted optofluidic reactors

Abstract

Research is being conducted on photocatalyst-based organic compound treatment processes for water purification to decompose wastewater efficiently. An optofluidic reactor based on TiO2 photocatalysis and nanoelectrokinetics was presented recently to improve the efficacy of photocatalytic water purification. However, inefficient absorption of visible light by TiO2 materials hinders the effective utilization of solar energy. To address this issue, the uniform formation and characterization of Au/TiO2 nanoparticles for a plasmonic photocatalytic-based optofluidic platform are studied to improve photocatalytic reactivity in visible light. The present study uses UV irradiation and spray spraying for producing Au/TiO2 NPs uniformly on microporous carbon fabric. Energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used to assess the quality of the Au/TiO2 NP-coated carbon fabric. Au NPs were uniformly obtained on the surface and inside the TiO2 coating layer by UV irradiation-based photo-reduction, according to SEM and TEM investigation. The interaction of Au NPs, TiO2 NPs, and carbon fabric (CF) to improve electron transport and charge separation on the photocatalyst surface is supported by XPS spectra. TEM and XRD analyses revealed that all TiO2 components in the Au/TiO2 coating layer consisted of anatase having high photocatalytic activity. After comparing the photocatalytic activity of TiO2 and Au/TiO2-coated samples under solar-simulated light and a voltage of 3 V, it was found that the surface coated with Au NPs had a superior photocatalytic effect than the surface coated with only TiO2.