Directional and Adaptive Oil Self-Transport on a Multi-Bioinspired Grooved Conical Spine

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.