The wettability of gas bubbles: from macro behavior to nano structures to applications.

In recent years, various interfaces related to bubble wettability have been fabricated, which have already been widely applied in various disciplines and fields. Therefore, to better research and understand the wettability of gas bubbles, recent progress with interfaces and wettability of bubbles in aqueous media, including superaerophilicity and superaerophobicity, is summarized. Many biological interfaces which exhibit marvelous characteristics are discussed for reference. Because of the similar behavior between gas bubbles in aqueous media and droplets in air, the two wetting conditions are compared together to better illustrate theories of gas bubble wettability. Based on these theories, effective and available manipulation of gas bubbles' wettability provides a novel idea and method to solve practical problems in various aspects, i.e., superaerophobic electrodes for gas evolution reactions, superaerophilic electrodes for gas compensation reactions, superaerophilic interfaces for directional collection and transportation of gas bubbles, and so on.