Enhanced catalytic activity of WO 3 –Au nanotubes: mechanism and environmental remediation potential

Environmental pollution treatment is a pressing global issue, and the development of eco-friendly and cost-effective pollution remediation technologies is crucial. We reported the synthesis and full characterization of WO 3 nanotubes, featuring a diameter of 10–15 nm and lengths extending up to several micrometers. Spherical Au nanoparticles (NPs) grew randomly on the surface of the WO 3 nanotubes. These nanotubes were employed for the photocatalytic degradation of the organic contaminant Rhodamine B. Notably, the WO 3 –Au nanotubes exhibited exceptional performance in the adsorption and photodegradation of Rhodamine B, achieving an impressive 95.6% removal rate. This enhancement can be attributed to the effective separation of photogenerated charge carriers, the extension of light absorption into the visible region, and the surface plasmon resonance (SPR) effect and Schottky barrier formed by the Au nanoparticles. The proposed photocatalytic mechanism explains the step-by-step degradation of Rhodamine B by utilizing the unique properties of the nanotubes. Recycling experiments demonstrated the stability of the photocatalyst, highlighting its potential for water purification applications. These findings emphasize the promising role of WO 3 –Au nanotubes as efficient photocatalysts for environmental remediation.