The invention relates to a structure, comprising a substrate supporting a layer with a photocatalytic and anti-soiling property, said layer being based on titanium dioxide (TiO2), on at least part of the surface thereof. Said structure is characterized in that the photocatalytic layer is coated with a non-porous thin layer, containing silicon and oxygen and having a coating capacity, providing a chemical and mechanical protection to the underlying photocatalytic layer, while maintaining the TiO2 photocatalytic activity.