Underwater Superaerophobic and Superaerophilic Nanoneedles‐Structured Meshes for Water/Bubbles Separation: Removing or Collecting Gas Bubbles in Water

: Water/bubbles separation has great practical significance, which can avoid the harm caused by underwater bubbles or cleverly collect useful gas bubbles in water. Here, a Cu(OH)2-nanoneedles-structured rough copper mesh is fabricated by a one-step chemical reaction. The original rough mesh shows superhydrophilicity in air and superaerophobicity in water. The underwater superaerophobic mesh has great anti/removing-bubbles ability in water. In contrast, the rough mesh switches to superhydrophobicity in air and superaerophilicity in water after further being modified with fluoroalkylsilane. The underwater superaerophilic mesh can absorb bubbles and allow bubbles to pass through the mesh. Based on the superhydrophilic/superaerophobic mesh and the superhydrophobic/superaerophilic mesh, a strategy to remove gas bubbles from the water pipe is proposed, and an in-water bubbles-collection device is also designed. It is believed that these two kinds of mesh will have more applications in controlling the behavior of underwater bubbles.