Efficient anti-frosting on discrete nanoclusters via spatiotemporal control of condensation frosting dynamics

Abstract

Tailoring the condensation frosting dynamics, particularly by surface topological designs, holds great promise to mitigate the frost accretion yet has proven challenging due to the complex and dynamic nature of interactions between vapor/liquid and surfaces. Herein, we propose a design of nanowire cluster (NC) isolated by grooves to spatiotemporally regulate the multiphase changes. The key feature lies in the integration of in-plane wetting discreteness and out-of-plane vapor flux gradient on the NC surface. By precise controlling the topology, e.g., in the case of vertex angle ∼ 30° and solid–liquid fraction ∼ 31%, the NC surface can spatially localize condensates on the cluster edges in stable Cassie state under both normal or low pressures, and temporally facilitate the removal of droplets at the minimized size even under −12 °C. Whereas the remaining droplets presented reduced mean size and a large spacing, which hindered inter-droplet ice bridging and droplet freezing. Notably, the sum of anti-frosting and frosting durations reached ∼ 200 min, which was ∼ 3 and ∼ 4 folds of other surfaces, at a temperature of −8 °C and relative humidity of ∼ 50%.