On the morning of 16 October, Doctoral Researcher Nguyễn Thế Luân successfully defended a doctoral thesis in Materials Science at VNUHCM–University of Science (HCMUS), entitled “Fabrication and Evaluation of the Photocatalytic Performance of Iron-Doped WO₃ on a Diatomite Support for Antibiotic Removal from Water”. The research was supervised by Assoc. Prof. Phạm Văn Việt and Assoc. Prof. Lê Tiến Khoa.

cused on developing composite materials with adsorption and photocatalytic properties for removing antibiotic compounds from water. The research aimed to establish a process for activating raw diatomite, synthesising iron-doped WO₃ through a hydrothermal method, and immobilising the photocatalyst on the diatomite surface.

The study examined the effects of iron (Fe) doping on the structure and photocatalytic activity of WO₃. The results indicated that iron doping could improve crystallinity, broaden light absorption through changes in band-gap energy, increase charge-carrier density and suppress the recombination of photogenerated electron–hole pairs. These properties contribute to enhanced photocatalytic performance.

A notable finding was the synergistic effect between the adsorption capacity of diatomite and the photocatalytic activity of iron-doped WO₃, particularly when H₂O₂ was added. Under the optimised material composition investigated — comprising 10% by mass of 7% Fe₃-doped material supported on diatomite — the composite achieved 57.1% removal of tetracycline from solution after 180 minutes of treatment.

In addition to antibiotic removal efficiency, the study assessed changes in total organic carbon (TOC) levels and the antibacterial activity of the treated solution. The results showed a reduction in total organic carbon content alongside a decline in antibacterial activity, evidenced by smaller inhibition zones. These indicators are important for evaluating antibiotic degradation and changes in the properties of residual substances following treatment.

The thesis also proposed several directions for further research to improve the material’s practical applicability. These include testing the 10% WF7-D material in combination with H₂O₂ in real wastewater treatment systems; optimising the preparation process to improve material durability and maintain treatment efficiency; and standardising the synthesis process for large-scale production.

The findings contribute to the scientific understanding of adsorption–photocatalytic materials for treating antibiotic-contaminated water. This research offers promising prospects for developing material-based solutions to remove persistent organic compounds from aquatic environments, supporting more effective water resource management and protection.