Facile synthesis of ZnO-clay minerals composites using an ultrasonic approach for photocatalytic performance

•Ultrasound-assisted method was successfully applied in ZnO-based composites synthesis.•ZnO-Pal, ZnO-Hal and ZnO-Pal/Hal composites showed high photocatalytic activity for ciprofloxacin degradation under visible light.•The immobilization of ZnO nanoparticles in the structure of clay minerals probably favors the photocatalytic activity under visible light.•The synergistic effect of the combination between semiconductor nanoparticles and the structure of clay minerals can promote the separation of charges and reduce recombination, and enhance the photocatalytic potential of for ZnO-Pal/Hal.