Synthesis and characterization of three-dimensional sea urchin-like AgBr/TiO2 microspheres with enhanced antibacterial and visible-light photocatalytic performance

Three-dimensional (3D) AgBr/TiO 2 microspheres with remarkable sea urchin-like architectures were prepared by a solvothermal-hydrothermal two-step process. The products have been characterized through XRD, SEM, HRTEM and Nitrogen adsorption–desorption analysis. The antibacterial activity of the 3D AgBr/TiO 2 microspheres against Escherichia coli ( E. coli ) was investigated quantitatively by microcalorimetric method for the first time. Meanwhile, the visible-light photocatalytic performance of the 3D AgBr/TiO 2 microspheres was also evaluated for the degradation of rhodamine B (RhB). As a contrast, the same tests were carried out for the conventional AgBr/P25 (TiO 2 ). The results show that the 3D AgBr/TiO 2 microspheres prevent better antibacterial and visible-light photoctalytic performance than the conventional AgBr/P25. It revealed that unique morphology effect, the extraordinary visible-light responses of AgBr and various oxidative radicals produced by visible light irradiated 3D AgBr/TiO 2 microspheres are responsible for improved antibacterial and photocatalytic performance.