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Heterogeneous surfaces with wetting contrast have gained extensive attention in recent years because of their potential application in condensation heat transfer enhancement. In this work, we engineered superhydrophobic/hydrophilic hybrid (SHH) surfaces on copper substrates via a laser-ablation process. We demonstrated that the as-fabricated SHH surfaces present dropwise condensation behavior; the condensate droplet growth, departure, and heat transfer performance depend strongly on the spacing of the hydrophilic spot. The surface with the hydrophilic spot spacing of 100 μm (SHH100) exhibits the most efficient dropwise condensation in terms of fast droplet growth rate, efficient coalescence-induced droplet departure, as well as enhanced heat transfer coefficient (HTC) compared to the homogeneous superhydrophobic (SHPo) surface. The mechanism underlying the enhanced condensation heat transfer performance is analyzed. A 12% enhancement on condensation HTC was found was found on SHH100 surface compared with the SHPo surface. Our results provide important insights for the design of hybrid surfaces with wetting contrast for enhancing condensation heat transfer performance in many industrial applications.

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Proton transport is involved in many biological processes, such as viral replication and enzymatic catalysis. However, one-way transmission is the premise of the realization of the above functions. Actually, the unidirectional transport of protons is significant not only for biology but also for practical applications. Herein, inspired by the influenza A M2 channel, a sub-nanoporous proton transport membrane was constructed by layer-by-layer assembly of two oppositely charged pillar­[n]­arenes with sub-nanometer cavities. A good selectivity of the proton transport membranes to protons was achieved by exploiting the size effect of sub-nanometer pores. And the proton transport membrane has a transport capacity of 459 μM·m–2·h–1 for protons. For nanofluidic diodes, the construction of the sub-nanopore proton transport membrane was very meaningful. For energy conversion applications such as catalytic transformations, although the flux cannot meet the application in these fields, the development of this membrane provides an idea for it. What is more, it can help deepen the understanding of the relationship between sub-nanostructure and function.