Hydrophilic–hydrophobic hybrid wettability structures, inspired by desert beetles, have been widely designed to enhance the dewdrops’ migration under subcooled or/and high-humidity environment. However, it is still a challenge to regulate the graded distribution of the hydrophilic micro-regions for condensation applications. In this paper, we design a simple spray method to prepare the superamphiphilic–superamphiphobic hybrid wettability coatings by controlling the mass ratio (MR) of superamphiphobic SiO2 nano-powder and superamphiphilic gypsum micro-powder. We compare the macroscopical wettability, condensation heat transfer efficiency, frosting delayed time and water harvesting rate to demonstrate the unique advantage of hybrid wettability structures. The results show that the condensation heat transfer efficiency, frosting delayed time and water harvesting rate can be respectively promoted to about 131.50% [Formula: see text], 134.74% [Formula: see text] and 135.62% [Formula: see text], although their macroscopical wettability will gradually reduce with the MR increase. This work will provide substantial insights into the fabrication of efficient superhydrophilic–superhydrophobic hybrid wettability surfaces for condensation heat transfer, anti-frosting and water harvesting applications.

Systematic regulation of hydrophilic regions plays a key role in optimizing the heterogeneous hydrophilic-hydrophobic surface for promoting condensate transfer ability (CTA) under subcooling or high-humidity conditions. In this work, we develop an operable method to fabricate wettability-controllable coatings by regulating the mass ratio of superamphiphobic and superamphiphilic powder (MRP). By investigating the synergic relationship between CTA and MRP, we display an interesting competition between condensation and detachment of condensates. The initial dewing rate associated with reflecting phase change heat transfer capacity could be continuously strengthened by promoting MRP, while the detachment capacity with respect to improving the long-term condensing rate can be limited by the excessive superamphiphilic microregions. Based on this, we have optimized the threshold of MRP for promoting the condensation heat transfer ability and the water harvesting efficiency with the values of 10:0−8:2 and 10:0−4:6, respectively. This work provides important guidance in designing and optimizing heterogeneous hydrophilic-hydrophobic surfaces for multiple industrial applications including heat management, water harvesting, and desalination.