Bio-inspired design of a transparent TiO2/SiO2 composite gel coating with adjustable wettability

Although the superhydrophobicity and transparence are generally two contradictory characters as the roughness factor, it is literature abundant for achieving both of these two purposes. To our knowledge, the integration multipurpose (transparent, superhydrophobic, superhydrophilic, underwater superoleophobicity, anti-fogging, and photo-controllable ability) in one has not been reported so far and these are vital for their promising applications in various aspects which can attract broad attention from scholars to engineers. In this work, we are successful to bio-inspired design of a kind versatile transparent nanocoating with superhydrophobic or superhydrophilic/underwater superoleophobic properties. The TiO2/SiO2 nanocoatings can be transformed from superhydrophobicity into superhydrophilicity and underwater superoleophobicity after heat treatment (450 degrees C and 2 h). If it was coated on conductive glass, the electrical conductivity was impervious, while the wettability can be manipulated. Importantly, both these superhydrophobic and superhydrophilic TiO2/SiO2 composite nanocoatings were endowed with photo-induced self-cleaning nature and these antifouling coatings could prolong their service life.