Biomimetic Multi Functional Superamphiphobic FOTS TiO2 Particles beyond Lotus Leaf.
It is widely known that natural examples like lotus leaves can only repel room temperature water but cannot repel hot water and oils. Even though superamphiphobic surfaces composed of re entrant "mushroom like" or "T shaped" structures are promising, they are generally regarded as substrate dependent and difficult to fabricate, and hence, their practical use on various materials has been limited. Here, we synthesize a flower like superamphiphobic FOTS TiO2 powder by solvothermal process and self assembly functionalization. These structured and functionalized submicron particles can repel the liquids with surface tension as low as 23.8 mN*m 1 (n decane) which is the lowest among powder samples. With respect to the biomimetic aspect, the surface morphology of FOTS TiO2 particle is similar to the hierarchical micro/nano structures of the lotus leaf surface, but it is beyond the lotus leaf for superoleophobic capacity. The difference in the oleophobicity is suggested to be the interplay of quasi spherical re entrant structure and perfluorined modification. Because of superior superamphiphobicity of the powder, a facile yet versatile strategy is developed, adhesive assisted sieve deposition fabrication (AASDF) for preparing superamphiphobic coatings on various substrates. The investigation results pertaining to the water/oil proofing, mechanical durability, self cleaning, and antifouling performances prove that the FOTS TiO2 coating is robust and multifunctional, which will enable more opportunities for practical applications. Apart from these general applications, we find that the superamphiphobic FOTS TiO2 powders when coated on sponge as anti icing surface have good ice delay and icephobic performances. Furthermore, they can be used to prepare magnetic Fe3O4&FOTS TiO2 composite particles through liquid marbles, implying significant scientific value.
ACS applied materials interfaces