Functionalization of cotton fabrics with plasmonic photo-active nanostructured Au-TiO₂ layer

A simple approach to functionalize cotton fabrics with Au and TiO₂ nanostructured layer is presented. Hybrid fabrics (Cot-Au-TiO₂) are prepared through reduction of AuCl₄^- on cotton, followed by a non-aqueous sol-gel procedure using tetrabutyltitanate and a hydrothermal treatment at 110°C. The generation of crystalline TiO₂ is confirmed by Raman spectroscopy. The fibres morphology and their roughness are characterized by AFM and FE-SEM. XPS shows how the concentration of the NPs precursors (Au and TiO₂) affects the layer composition. GSDR (Ground State Diffuse Reflectance Absorption Spectroscopy) and LIL (Laser induced luminescence) reveal a strong quenching effect induced by Au NPs. Photocatalytic activity measured through the Remazol Blue (RB) degradation reveals an enhancement under visible light, which increases with Au loading. This strong enhancement is explained through the surface plasmon resonance brought by Au NPs.