Bioinspired surfaces for directional liquid transport: design and manufacturing

Controllable directional liquid transport, as a promising form of intelligent liquid manipulation, plays an important role in many fields. In nature, directional liquid transport properties are found on a wide variety of biological surfaces, such as the Namib Desert beetle, cactus and Crassula muscosa, etc. Learning from nature provides great inspiration for researchers to solve engineering problems. In this review, the classical directional transport mechanisms, including the wettability gradient and the Laplace pressure difference, are introduced. Then, from single to multiple biomimetic surfaces, the design and manufacturing are reviewed in detail through some representative examples. Finally, some challenges faced in the current development of bioinspired surfaces are summarized.