Effect of Ag Modification on the Structure and Photocatalytic Performance of TiO(2)/Muscovite Composites

Ag/TiO(2)/muscovite (ATM) composites were prepared by the sol–gel method and the effects of Ag modification on the structure and photocatalytic performance were investigated. The photocatalysts were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller surface area (BET), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FTIR), photoluminescence spectra (PL) and ultraviolet–visible diffuse reflectance spectra (DRS). The photocatalytic activity of the obtained composites was evaluated by taking 100 mL (10 mg/L) of Rhodamine B (RhB) aqueous solution as the target pollutant. The muscovite (Mus) loading releases the agglomeration of TiO(2) particles and the specific surface area increases from 17.6 m(2)/g (pure TiO(2)) to 39.5 m(2)/g (TiO(2)/Mus). The first-order reaction rate constant increases from 0.0009 min(−1) (pure TiO(2)) to 0.0074 min(−1) (150%TiO(2)/Mus). Ag element exists in elemental silver. The specific surface area of 1-ATM further increases to 66.5 m(2)/g. Ag modification promotes the separation of photogenerated electrons and holes and increases the visible light absorption. 1%Ag-TiO(2)/Mus (1-ATM) exhibits the highest photocatalytic activity. After 100 min, the rhodamine B (RhB) degradation degrees of PT, 150%TiO(2)/Mus and 1-ATM are 10.4%, 48.6% and 90.6%, respectively. The first-order reaction rate constant of 1-ATM reaches 0.0225 min(−1), which is 25 times higher than that of pure TiO(2).