Photocatalytic and photodisinfectant activity of sulfated and Eu doped anatase against clinically important microorganisms

Surface sulfation and Eu3+ doping of 0.2–2 µm anatase aggregates prepared by precipitation significantly increased their porosity, specific surface, crystallinity and photocatalytic activity in phenol photo-mineralization. Such large, porous clusters of photocatalysts containing nanocrystals with well developed crystallinity which sediment more quickly than nanopowder suspensions are advantageous in water treatment applications. Sulfated anatase co-doped with Eu3+ exhibited the highest photoactivity. This is composed of well developed crystallites in the 31–55 nm size-range, with evident faceting. Although the investigated powders showed very weak photo-disinfectant activity against Gram-negative Escherichia coli rods, they exhibit moderate efficacy against Gram-positive bacterial strains of methicillin resistant Staphylococcus aureus (MRSA) and Enterococcus faecalis. The investigated powders, especially the Eu3+ doped ones, are highly active in elimination of the eukaryotic Candida albicans.