Directional Transportation Behavior of Droplets on a Magnetically Responsive Micropillar Array Surface.

Technologies for manipulating droplets have applications in various fields, such as biomedical devices, chemical engineering, water collection, and thermal management. The morphology of magnetically responsive surfaces are modified using magnetic fields for inducing droplet directional rolling and bouncing. Herein, a study on the directional transport of droplets on magnetically responsive surfaces is reported, identifying three movement modes and analyzing the mechanisms influencing the transport behavior. The study explored working fluids with surface tension lower than that of water, achieving the directional transport of 30% ethanol droplets with a maximum transport velocity of 130 mm s. The practical applications of the droplets on a modified surface were analyzed, and methods were developed to accelerate droplet mixing. This study explored efficient operations and automation of complex chemical processes.