Enhanced photocatalytic activity of TiO2-loaded composite oxides with different Cu–Cu2O–CuO ratios derived from CuZnAl layered double hydroxides

Photocatalysis technologies for degrading organic pollutants have emerged as a promising strategy for environmental remediation. This study aimed to develop efficient photocatalysts by synthesizing TiO 2 -loaded composites derived from CuZnAl layered double hydroxides (LDHs) and assessed their performance in the decomposition of rhodamine B (RhB). CuZnAl-LDH nanosheets were synthesized via coprecipitation and then calcined at high temperatures to obtain CuZnAl layered double oxides (CZA-LDO). By varying the amount of ascorbic acid, the CuO in CZA-LDO was reduced to different extents, thereby varying the ratio of Cu, Cu 2 O and CuO. TiO 2 was then deposited on the surface. The morphology, crystal structure, bonding state, and photocatalytic performance of the composite materials were assessed. When exposed to UV light, the optimized TiO 2 /Cu–Cu 2 O–CuO–0.7 composite material achieved a degradation rate of 96.0% for RhB within 110 min, which was significantly better than TiO 2 /CZA-LDO (46.0%) and other Cu-modified samples (66.2%–77.9%). The enhanced photocatalytic properties of the prepared nanocomposite were ascribed to doping with Cu, Cu 2 O and CuO, which effectively enhanced the electron–hole pair separation efficiency. These findings demonstrate the potential of Cu-Cu 2 O-CuO-LDO-based photocatalysts as effective materials for degrading organic contaminants in environmental remediation. Graphical abstract