Robust underwater
oil-repellent materials combining high
mechanical
strength and durability with superwettability and low oil adhesion
are needed to build oil-repellent devices able to work in water, to
manipulate droplet behavior, etc. However, combining all of these
properties within a single, durable material remains a challenge.
Herein, we fabricate a robust underwater oil-resistant material (Al2O3) with all of the above properties by gel casting.
The micro/nanoceramic particles distributed on the surface endow the
material with excellent underwater superoleophobicity (∼160°)
and low oil adhesion (<4 μN). In addition, the substrate
exhibits typical ceramic characteristics such as good antiacid/alkali
properties, high salt resistance, and high load tolerance. These excellent
properties make the material not only applicable to various liquid
environments but also resistant to the impact of particles and other
physical damage. More importantly, the substrate could still exhibit
underwater superoleophobicity after being worn under specific conditions,
as wear will create new surfaces with similar particle size distribution.
This approach is easily scalable for mass production, which could
open a pathway for the fabrication of practical underwater long-lasting
functional interfacial materials.