Layered Nanocomposite 2D-TiO 2 with Cu 2 O Nanoparticles as an Efficient Photocatalyst for 4-Chlorophenol Degradation and Hydrogen Evolution

New composites formed by layered hybrid TiO 2 (stearic acid) (LHTiO 2 ) and, Cu 2 O nanoparticles were studied as photocatalysts that extend the response range to light visible for the evolution of hydrogen and the degradation of 4-chlorophenol. The results revealed that LHTiO 2 /Cu 2 O exhibited a clearly improved photocatalytic degradation, about 5.6 times faster than pristine TiO 2 , and hydrogen evolution of about 2.7 times higher than the TiO 2 anatase. The enhanced photocatalytic activity can be assigned to the properties of the two-dimensional morphology, in sheets-like arrangement of LHTiO 2 , benefitting from the high exposure of surface, with more active sites available to improve matching with the surfaces of the Cu 2 O nanocrystals and significant reduction of migration distances of photogenerated carriers. In the photocatalytic degradation, a mechanism Z-scheme is supported, and in the photocatalytic evolution of hydrogen a mechanism type II band alignment is indicated. Photocatalytic reuse tests showed that stability and catalytic activity of LHTiO 2 /Cu 2 O were maintained for three cycles. Photoelectrochemical evaluation were performed through measurements of the photocurrent response and electrochemical impedance.