Extended Data Fig. 4: Wrapping layers around a water droplet in air and in a hydrocarbon on FLIPS, and the ability of the macroscopic protuberance to hold a droplet at tilt angles.
From: Multifunctional ferrofluid-infused surfaces with reconfigurable multiscale topography
a, Photographs of a water droplet (about 5 μl) placed on a FLIPS with ferrofluid 1 (left) and diluted ferrofluid 1 (right). b, Photographs of a water droplet (about 5 μl) placed on a FLIPS with ferrofluid 1 (left) and diluted ferrofluid 1 (right) immersed in dodecane. c, Photographs of a water droplet (about 5 μl) held by a magnet at about 90° and 30° on a FLIPS with ferrofluid 1 (left) and diluted ferrofluid 1 (right), respectively. d, Photographs of a water droplet (about 5 μl) immersed in dodecane and held by a magnet at about 90° and 30° on a FLIPS with ferrofluid 1 (left) and diluted ferrofluid 1 (right), respectively. The comparison between c and d suggests that holding a droplet on the macroscopic protuberance does not require the existence of the wrapping layer and that capillary force is likely to dominate the interaction.
