Characterization of the structure and catalytic activity of copper modified palygorskite/TiO2 (Cu2+-PG/TiO2) catalysts

Titanium dioxide coated on copper modified palygorskite clay nanocomposite (Cu2+-PG/TiO2) prepared by hydrolysis method was used as photocatalyst in the degradation reaction of methylene blue. The surface characteristics of copper modified palygorskite coated with TiO2 particles was confirmed by the X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), Brunauer–Emmett–Teller (BET) surface area analysis and X-ray photoelectron spectrometer (XPS). The incorporation of Cu2+ did not change the structure of the palygorskite. The size of anatase particles was relatively small (<5 nm) and highly dispersed in the solid palygorskite fibrous clay. Surface areas of Cu2+-PG/TiO2 as high as 198.6 m2/g were measured for catalysts containing 0.6 wt.% copper and 25 wt.% titanium dioxide. The photocatalytic activity of those nanocomposite photocatalysts was much higher than that of the pure titanium dioxides.