Superhydrophobicity of LaMnO₃ Coatings with Hierarchical Microstructures

As proposed by Herminghaus, a hierarchical structure could render any surface nonwettable as long as the roughness amplitude at small scales is sufficient to suspend a free liquid surface. Recently we reported that the wettability of La_0.7Sr_0.3MnO₃, an intrinsic hydrophilic oxide, can be tuned from superhydrophilicity to superhydrophobicity by hierarchical microstructures generated by annealing the coatings of La_0.7Sr_0.3MnO₃ powder in nanometric scale at different temperatures. Here we further demonstrate the similar phenomenon observed on LaMnO₃ coatings, which conforms THAT the surface
geometrical structure is a key factor to determine the wettability.