Natural evolution has endowed diverse species with distinct geometric micro/nanostructures exhibiting admirable functions. Examples include anisotropic microgrooves/microstripes on the rice leaf surface for passive liquid directional rolling, and motile microcilia widely existed in mammals’ body for active matter transportation through in situ oscillation. Till now, bionic studies have been extensively performed by imitating a single specific biologic functional system. However, bionic fabrication of devices integrating multispecies architectures is rarely reported, which may sparkle more fascinating functionalities beyond natural findings. Here, a cross-species design strategy is adopted by combining the anisotropic wettability of the rice leaf surface and the directional transportation characteristics of motile cilia. High-aspect-ratio magnetically responsive microcolumn array (HAR-MRMA) is prepared for active droplet transportation. It is found that just like the motile microcilia, the unidirectional waves are formed by the real-time reconstruction of the microcolumn array under the moving magnetic field, enabling droplet (1–6 μL) to transport along the predetermined anisotropic orbit. Meanwhile, on-demand droplet horizontal transportation on the inclined plane can be realized by the rice leaf-like anisotropic surface, showcasing active nongravity-driven droplet transportation capability of the HAR-MRMA. The directional lossless transportation of droplet holds great potential in the fields of microfluidics, chemical microreaction, and intelligent droplet control system.

Manipulating oil droplets in an aqueous solution offers great opportunities to develop advanced devices in the fields of water remediation, chemical micro-reactor, etc. Although conical structures can achieve a directional oil droplet motion, the continuous and adaptive fluid self-transport in complicated environments is still a challenge. Inspired by the distinctive oil transport capability of fishbone and the anisotropic grooved structure of rice leaves, this work presents a multi-bioinspired grooved conical spine (BGCS) for improved oil manipulation. Benefiting from the cooperative effect of the asymmetric Laplace pressure and the surface capillary force, the BGCS possesses the reliable functions of ultrafast and continuous oil transport under water, in air, and even across the air-water interface. Compared with the original cone, the BGCS demonstrates a nine times faster transporting velocity and a five times larger capacity. It is envisioned that this updated oil-collecting cone with its cooperative structure should find real-world applications.

Natural organisms can create various microstructures via a spontaneous growth mode. In contrast, artificial protruding microstructures are constructed by subtractive methods that waste materials and time or by additive methods that require additional materials. Here, we report a facile and straightforward strategy for a laser-induced self-growing mushroom-like microstructure on a flat surface. By simply controlling the localized femtosecond laser heating and ablation on the poly(ethylene terephthalate) tape/heatshrinkable polystyrene bilayer surface, it is discovered that a mushroom-like architecture can spontaneously and rapidly grow out from the original surface within 0.36 s. The dimension of the reentrant micropillar array (cap diameter, pillar spacing, and height) can be accurately controlled through the intentional control of laser scanning. Followed by a fluorination and spray coating, the obtained surface can realize the repellency and manipulation of oil droplets. This work provides new opportunities in the fields of microfabrication, microfluidics, microreactor engineering, and wearable antifouling electronics.

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