Synthesis, characterization, and photocatalytic antibacterial activities of porous Ce-doped TiO2 microspheres using pine pollen as novel biotemplates

Abstract

Using pine pollen as a new biological template, Ce-doped TiO2 porous microspheres were prepared via the sol–gel method and impregnation method after high-temperature calcination. The samples were characterized using scanning electron microscopy, X-ray energy spectrum analysis, X-ray diffraction, UV–Vis diffuse reflectance spectroscopy, photoluminescence spectroscopy, electrochemistry, and electron spin resonance spectroscopy. Owing to the doping of cerium, the bionic material showed a better photocatalytic antibacterial performance, and the antibacterial rate against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis surpassed 99.9% within 120 min under xenon lamp irradiation. In addition, we discuss the photocatalytic sterilization mechanism of porous Ce-doped TiO2 microspheres. The antibacterial activities of this biomimetic material are mainly due to the reactive oxygen species produced by its photocatalysis; these species attack bacteria, causing them to cleave and die. Inspired by natural pollen, the materials were prepared, and they have broad application prospects for photocatalytic disinfection. Graphical abstract: [Figure not available: see fulltext.]