Reinigen mit Licht und Regen

After the discovery of the lotus‐effect in the 1970s the attention concerning the field of self‐cleaning surfaces increased rapidly. Besides hydrophobic surfaces which are designed following the example of the lotus flower, superhydrophilic and photocatalytic active coatings play an important role. These coatings are using sunlight to oxidize pollutants and remove residues by rinsing with water. Coatings based on the lotus‐effect suffer from their weak mechanical durability, but are able to work without light. On the other hand, photocatalytic layers are mechanically stable, but they need to be illuminated to become self‐cleaning.