The flexible manipulation of underwater gas bubbles on
solid substrates
has attracted considerable research interest from scientists in the
fields of water electrolysis, bubble microreactions, drug delivery,
and heat transfer. Inspired by the oxygen-binding mechanisms of aquatic
organisms, scientists have designed a series of interfacial materials
for use in collecting gases, detecting and grading bubbles, and conducting
microbubble reactions. Aerophilic surfaces are commonly used in underwater
bubble manipulation platforms due to their excellent gas-trapping
properties. However, during bubble transport, some of the bubbles
are retained in the rough structure of the aerophilic surface and
cause gas loss, which in the long run reduces the gas transport function.
In addition, the aerophilic surface is prone to failure in high-humidity
and high-pressure underwater environments. The lubricant-infused surface
features an oil layer that remains stable on a rough substrate and
is immiscible with water. Additionally, the bubbles are transported
over the oil layer without causing losses other than those dissolved
in water. These attributes make it more favorable than the aerophilic
surface. Inspired by the unique properties of Nepenthes and cactus
spines, we developed a patterned slippery surface [patterned lubricant-infused
surface (PLIS)] through laser etching and ammonia etching that facilitates
the coexistence of superaerophobic and aerophilic surfaces. The PLIS
executes bubble capture utilizing a difference in wettability measuring
78°, transports bubbles through Laplace force and buoyancy, and
regulates bubble release by restricting the contact area on the PLIS.
The PLIS can be prepared rapidly and affordably in just about an hour,
and its potential for large-scale production is high. Following tests
for shear, acid and alkali resistance, and corrosion resistance, the
PLIS exhibited impressive weathering resistance and appears to have
potential for application in some extreme environments.