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Achieving effective dropwise capture and ultrafast water transport is essential for fog harvesting. In nature, cactus uses the conical spine with microbarbs to effectively capture fog, while Sarracenia utilizes the trichome with hierarchical microchannels to quickly transport water. Herein, we combined their advantages to present a novel configuration, a spine with barbs and hierarchical channels (SBHC), for simultaneous ultrafast water transport and high-efficient fog harvesting. This bioinspired SBHC exhibited the fastest water transport ability and the highest fog harvesting efficiency in comparison with the spine with hierarchical channels (SHCs), the spine with barbs and grooves (SBG), and the spine with barbs (SB). Based on the fundamental SBHC unit, we further designed and fabricated a twodimensional (2D) spider-web-like fog collector and a three-dimensional (3D) cactus-like fog collector using direct laser structuring and origami techniques. The 2D spider-web and 3D cactus-like fog collectors showed high-efficient fog collection capacity. We envision that this fundamental understanding and rational design strategy can be applied in fog harvesting, heat transfer, liquid manipulation, and microfluidics.

The present work is devoted to investigating the effect of CeO 2 , PtO 2 and BaCeO 3 additives on the Y 2 BaCuO 5 morphology and the melt processing of YBCO. The samples were synthesized by the melt texture growth (MTG) process in order to observe the Y 2 BaCuO 5 morphology in the liquid phase at high temperature, in the YBa 2 Cu 3 O 7−x matrix resulting from the peritectic reaction, and the resulting microstructure of YBa 2 Cu 3 O 7−x . It is concluded that these investigated dopants exhibit similar effects concerning the limitation of Y 2 BaCuO 5 coarsening in the melt. The evolution of the aspect ratio (l /w ) versus the additive content in the melt demonstrates the change of the morphology of the Y 2 BaCuO 5 grains. The magnetization measurements were carried out on cleaved samples using a SQUID magnetometer at 77 K with H c axis. The best compromise between an homogeneous and submicrometre Y 2 BaCuO 5 distribution through the textured area and a high critical current density corresponds to either 'YBa 2 Cu 3 O 7−x + 20 mol% Y 2 BaCuO 5 + 2 wt% CeO 2 ' or 'YBa 2 Cu 3 O 7−x + 20 mol% Y 2 BaCuO 5 + 0.5 wt% PtO 2 '. The distinct effects of cerium and platinum dopings on the superconducting properties are revealed by the critical current density J c measurements. Indeed, the cerium doped sample exhibits a J c = 5.5 × 10 4 A cm −2 in zero field with a relatively important field dependence behaviour: J c (1 T)/J c (0) = 40%. In contrast the platinum doped sample strongly reduces this field degradation of J c with J c (1 T)/J c (0) = 80%.