Surface plasmon resonance-enhanced solar-driven photocatalytic performance from Ag nanoparticle-decorated self-floating porous black TiO2 foams

Abstract Ag nanoparticle-decorated self-floating porous black TiO2 foams (Ag-FBTFs) are fabricated by facile wet-impregnation and high-temperature surface hydrogenation strategy, utilizing self-floating porous black TiO2 foams (FBTFs) with 3D macro-mesoporous architectures as hosts. The composites are evidently investigated by X-ray diffraction (XRD), Raman, N2 adsorption, diffuse reflectance spectroscopy (DRS), transmission electron microscope (TEM), scanning electron microscopy (SEM), scanning Kelvin Probe (SKP), surface photovoltage spectroscopy (SPS) and photoluminescence (PL). The results show that the small Ag nanoparticles with diameter of 3–4 nm are decorated on the surface of FBTFs uniformly, which extend the photoresponse to visible-light region and show obvious surface plasmon resonance (SPR). The Ag-FBTFs exhibit excellent solar-driven photocatalytic performance for complete mineralization of some high-toxic organic contaminants. The enhancement can be attributed to the 3D macro-mesoporous networks facilitating the diffusion of reactants and products, the floating feature and small Ag nanoparticle-decoration favoring light-harvesting and spatial separation of photogenerated electron-hole pairs due to SPR effect. This novel SPR-enhanced solar-driven floating photocatalyst will have potential application in fields of natural environment.