In this work ,we characterize the photocatalytic and anti-
bacterial activity of TiO2 films deposited by ALD at different tem-
peratures . Photocatalytic activity was evaluated by the degrada-
tion of the organic compounds Methylene-Blue (MB) in water
under UV light irradiation .The antibacterial activity was tested on
Escherichia coli, a well-known Gram-negative bacterium ,through
CFUs count. E. coli is a representative of coliforms and it is con-
sidered to be an indicator of fecal contamination in drinking water