Smart water channelling through dual wettability by leaves of the bamboo Phyllostachys aurea, Colloids and Surfaces A: Physicochemical and Engineering Aspects http://dx. HIGHLIGHTS Dual hydrophobic-hydrophilic wettability of young Phyllostachys aurea bamboo leaf surfaces leads to water channelling and self-cleaning. Nanoscale roughness of epicuticular waxes combined with very-long-chain alkyl compounds underpin localised leaf wetting characteristics. Bioinspired replication of dual wetting hydrophobic -hydrophilic channelled surfaces may offer potential for fog collection and dew harvesting in water-scarce regions of the world. ABSTRACTThe young leaves of the bamboo plant, Phyllostachys aurea, exhibit a distinct dual wetting behaviour on their adaxial surface. Contact angle analysis, variable pressure (environmental) scanning electron microscopy, gas chromatography, time-of-flight secondary ion mass spectrometry, and X-ray photoelectron spectroscopy have shown that the epicuticular wax morphology/topography and the surface distribution of chemical species underpin this water-channelling behaviour. Envisaged bioinspired applications include fog and dew harvesting in water-scarce regions of the world.

Thuja plicata is a coniferous tree which displays remarkable water channelling properties. In this article, an easily fabricated mesh inspired by the hierarchical macro surface structure of Thuja plicata branchlets is described which emulates this efficient water collection behaviour. The key parameters are shown to be the pore size, pore angle, mesh rotation, tilt angle (branch droop) and layering (branch overlap). Envisaged societal applications include water harvesting and low cost breathable architecture for developing countries.