  A heat exchange interface at subzero temperature in a water vapor
environment, exhibits high probability of frost formation due to freezing
condensation, a factor that markedly decreases the heat transfer efficacy due
to the considerable thermal resistance of ice. Here we report a novel strategy
to delay ice nucleation on these types of solid-water vapor interfaces. With a
process-driven mechanism, a self-generated liquid intervening layer immiscible
to water, is deposited on a textured superhydrophobic surface and acts as a
barrier between the water vapor and the solid substrate. This liquid layer
imparts remarkable slippery conditions resulting in high mobility of condensing
water droplets. A large increase of the ensuing ice coverage time is shown
compared to the cases of standard smooth hydrophilic or textured
superhydrophobic surfaces. During deicing of these self-impregnating surfaces
we show an impressive tendency of ice fragments to skate expediting defrosting.
Robustness of such surfaces is also demonstrated by operating them under
subcooling for at least 490hr without a marked degradation. This is attributed
to the presence of the liquid intervening layer, which protects the substrate
from hydrolyzation enhancing longevity and sustaining heat transfer efficiency.
