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Slippery, liquid-infused porous surfaces offer a promising route for producing omniphobic and anti-icing surfaces. Typically, these surfaces are made as a coating with expensive and time consuming assembly methods or with fluorinated films and oils. We report on a route for producing liquid-infused surfaces, which utilizes a liquid precursor fed oxygen-hydrogen flame to produce titania nanoparticles deposited directly on a low-density polyethylene film. This porous nanocoating, with thickness of several hundreds of nanometers, is then filled with silicone oil. The produced surfaces are shown to exhibit excellent anti-icing properties, with an ice adhesion strength of ∼12 kPa, which is an order of magnitude improvement when compared to the plain polyethylene film. The surface was also capable of maintaining this property even after cyclic icing testing. Slippery, liquid-infused porous surfaces (SLIPSs) are nature inspired surfaces that are designed to repel liquid and solid materials. These surfaces have been shown to pose anti-icing properties, which broadens the available end-uses from the chemical industry to arctic transportation and energy production. The method behind repellency of SLIPSs relies on preventing outside liquids from penetrating the surface structure to the Wenzel state. Instead, the slippery liquid within the porous solid supports the Cassie-Baxter state (instead of air, here the porous structure is filled with lubricant), where the reduced area of the porous solid surface is available to interact with the liquid or ice to be repelled. The difference between Wenzel and Cassie-Baxter states is illustrated in Figure 1. This phenomenon is exploited in many superhydrophobic surfaces where an air cushion is entrapped within the porous solid surface. As a result, spherical water drops easily roll off the surface (and have static contact angles larger than 150°). publishedVersion

(Ba,Ca)(Ti,Zr)O3 solid solutions are promising lead-free piezoelectrics near their polymorphic phase boundary, which is believed to be linked to the interplay between B-site driven ferroelectricity and A-site driven ferroelectricity. Focusing on (Ba,Ca)TiO3, we support this picture from first-principles calculations. In particular, we show how steric effects related to the partial substitution of Ba by Ca largely enhance the Ca-driven ferroelectricity, already virtually allowed in the parent CaTiO3. The emergent interplay between the Ca-driven and Ti-driven mechanisms lowers the energy barrier between different polar states, which eventually results in a quasi-isotropic polarization under substitution of a small concentration of Ba by Ca. A sizeable enhancement of the piezoelectric response directly results from these features.(Ba,Ca)(Ti,Zr)O3 solid solutions are promising lead-free piezoelectrics near their polymorphic phase boundary, which is believed to be linked to the interplay between B-site driven ferroelectricity and A-site driven ferroelectricity. Focusing on (Ba,Ca)TiO3, we support this picture from first-principles calculations. In particular, we show how steric effects related to the partial substitution of Ba by Ca largely enhance the Ca-driven ferroelectricity, already virtually allowed in the parent CaTiO3. The emergent interplay between the Ca-driven and Ti-driven mechanisms lowers the energy barrier between different polar states, which eventually results in a quasi-isotropic polarization under substitution of a small concentration of Ba by Ca. A sizeable enhancement of the piezoelectric response directly results from these features.